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Eddie Norman
Jay Cubitt
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KEY STAGE 3 DESIGN AND TECHNOLOGY RESOURCE PACK
Flexible structures –
Kites
Philip Allan Publishers Limited
Market Place
Deddington
Oxfordshire OX15 0SE
First published 1999
ISBN 0 86003 229 9
© 1999 Philip Allan Publishers Limited
All rights reserved
Artwork and design by Juha Sorsa
Printed by Lindsay Ross, Abingdon
COPYRIGHT NOTICE
Any educational institution that has purchased one copy of this publication
may make duplicate copies for use exclusively within that institution.
Permission does not extend to reproduction, storage in a retrieval system, or
transmittal, in any form or means, electronic, mechanical, photocopying,
recording or otherwise, of duplicate copies for loaning, renting or selling to any
other institution without the prior consent in writing of the publisher.
The butterfly image on p.18 is reproduced by kind permission
of Breck P. Kent/Oxford Scientific Films.
The greetings card kites pictured on p. 28 are available from:
Kite Corner, 657 Watford Way, London NW7
The ‘Incredible Pocket Kite’ pictured on p. 28 can be obtained from:
Lagoon Games, PO Box 311, Kingston KT2 5QW
The image of the Flexifoil power kites on p. 51 is reproduced
by kind permission of Flexifoil International.
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Contents
Introduction .............................................................................................................. 1
Information Sheet (IS)1:
Construction of a ‘paper and artstraw’ original kite ............................................. 11
Section 1: Building a kite – a focused practical task
Teacher’s notes (TN)1 ............................................................................................. 12
Focused practical task (FPT)1–12 .......................................................................... 16
Information sheet (IS)2: Some interesting kite designs ....................................... 28
Section 2: Kite design – a design and make assignment
Teacher’s notes (TN)2 ............................................................................................. 29
Design and make assignment (DMA)1–17 ........................................................... 34
Information sheet (IS)3: Kites and materials ......................................................... 51
Section 3: IDEAs and extension tasks
Teacher’s notes (TN)3 ............................................................................................. 52
Materials and components (MC)1–5 ................................................................... 56
Structures (S)1–3 ..................................................................................................... 61
Science (Sc)1–4 ....................................................................................................... 65
Mathematics (M)1–2 .............................................................................................. 69
Information and communication technology (ICT)1–2 ...................................... 71
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Introduction
Authors
Eddie Norman is a senior lecturer in the Department of Design
and Technology at Loughborough University and has been
appointed co-director of IDATER (the International Conference on
Design and Technology Educational Research and Curriculum
Development). He was a co-author of the textbook Advanced Design
and Technology (Longman) and of a video series aimed at Key Stage 3
design and technology. Most recently, he was chief editor of the GCSE
magazine New Designer. He is also a guitar enthusiast.
Jay Cubitt is a part-time lecturer in the Department of Design and
Technology at Loughborough University. She was a co-author of
Advanced Design and Technology and is at present researching and
producing flexible learning materials in design and technology.
Jay has also spent the last 10 years pursuing research into the human
energy system. She is the founder member of Spectrum Healing,
which she practises and teaches in the UK and abroad. She also
enjoys music and Appalachian Dance.
About this pack
This resource pack has two essential aims:
◆ to provide the opportunity to meet National Curriculum (NC) requirements
through a broadly based, innovative approach;
◆ to facilitate designing through the visual representation of technology, where
possible.
The pack has a number of key objectives:
◆ to support the teaching and learning of design and technology at Key Stage 3 (KS3);
◆ to facilitate teaching and learning in relation to structures and materials and
components;
◆ to support cross-curricular links to art and design, information and communication
technology (ICT), humanities, mathematics and science;
◆ to support differentiation by providing extension tasks for the more able students and
revisiting opportunities for the less able ones.
The resource pack is targeted at the teaching of structures at KS3, but is flexibly organised
to allow the depth in many other areas to be varied depending on the available time and
the students’ capabilities, e.g. designing skills, making skills, materials and components,
quality and planning. It has been designed to fit into any one of Years 7, 8 or 9, which
allows teachers flexibility in fitting work in this area into their existing programmes. It has
been envisaged that the project would be one of approximately nine completed during
this Key Stage (see the SCAA model on page 2). A particular innovative feature of this pack
is the teaching of structures, which is traditionally regarded as ‘hard’ technology, through
work including ‘soft’ materials such as paper and textiles. Such ‘soft’ materials are not
always fully accepted as suitable for work in technology, and this resource pack seeks to
support the technological aspects of their use.
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KEY STAGE 3 DESIGN AND TECHNOLOGY RESOURCE PACK
Y7
Y8
Y9
UNIT 1
Play
UNIT 4
Communications
UNIT 7
Safety and security
2 Each unit reflects the main requirements
of the Programme of Study. Once each
unit has been organised on an individual
basis, the units are compared to check for
overall coverage and progression across
the key stage.
Source: SCAA (1995) Key Stage 3 Design and
Technology – The New Requirements.
UNIT 2
Community
UNIT 5
Manufacturing
UNIT 3
Retail world
1 Provisional
titles are chosen
for nine units
of work which
will provide
opportunities
for activities
in a range of
contexts.
UNIT 6
Transport
UNIT 5: MANUFACTURING
◆ Range of activities
◆ Designing
◆ Making
◆ Knowledge and understanding
– Materials
– Systems and control
– Structures
– Products and applications
– Quality
– Health and safety
SCAA model for Key Stage 3 design and technology
The National Curriculum requirements concerning structures at KS3 could be met
in a variety of ways, but kites offer a particularly rich context. Kites have been made
in schools for decades for the very good reason that they offer pupils an exciting
opportunity to explore designing and making. They have been the focus of work in
subject areas such as science and art and design, and there are well-known opportunities for many other cross-curricular links, e.g. to the humanities, ICT and
mathematics. This pack has been designed to develop these strengths, in supporting
the teaching and learning of KS3 design and technology. There are other flexible
structures that could be similarly addressed (e.g. carrier bags, shelters, umbrellas and
furniture), but kites have been selected as they seem to offer the richer opportunities.
A selection of briefs is provided on one of the photocopiable sheets (DMA4). The major
potential difficulty is the possibility of inclement weather conditions, and homework
probably provides the best means of overcoming this problem. Students can then test their
kites in their own time when the conditions are right.
There are many kite enthusiasts, and the potential interaction associated with kite
designing and making offers the opportunity to build useful links between the school and
the community.
The initial focused practical task – making and evaluating a kite constructed mainly from
recycled materials – is also a familiar theme, but this is one which echoes current design
movements. The Recycling exhibition, organised by the Crafts Council, toured the UK recently.
This and the Re(f)use exhibition in the USA have celebrated the work of many designers using
recycled materials. The International Design Resource Awards (IDRA) competition involves
designing with recycled materials and is organised from Seattle in the USA. It can be entered
by both professional and student designers, including school pupils. The World Wide
Web site is http://www.worldinc.com/idra/ – further information can be found there.
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Howard Gardner, in considering human rationality as part of his authoritative
account of the development of cognitive science, made the following
comments:
We can better understand the logical reasoning of humans not by imputing to
them any formal logical calculus but by attending instead to two factors. The
first has to do with content: the greater the familiarity and the richer the relevant schemata which are available, the more readily can one solve a problem. The
second attribute has to do with form: one succeeds on problems to the extent that
one can construct mental models that represent the relevant information in an
appropriate fashion and use these mental models flexibly. Just how one learns to construct such mental models, to integrate them with ‘real world’ knowledge, and to
deploy them appropriately in the proper circumstances are fertile questions for developmental and educational psychology.
Source: H. Gardner (1985) The Mind’s New Science: A History of the Cognitive Revolution, Basic Books Inc.,
pp. 369–70.
The connection between Gardner’s analysis and this resource pack concerning kite
design might not be immediately apparent, but it is real enough. Foundation studies –
focused practical tasks (FPTs) – improve familiarity of a particular technology and
context and help the construction of relevant schemata. The FPT presented here
provides the opportunity for lessons on drawing skills, materials recycling, forces,
structural members, understanding solutions evolved from nature, centre of gravity,
stability and safety issues, the making skills associated with kite building, the
basics of kite flying and the undertaking of systematic tests in order to troubleshoot
difficulties.
Teachers could spend a considerable amount of time on such topics, and could
start the design and make assignment (DMA) in parallel if they wish (choosing a
brief, developing a specification, etc.) DMAs seek to develop the ability to construct
appropriate mental models and use them flexibly. The pupils are encouraged here
to be as free-thinking and experimental as they can. The DMA is a learning
experience and they need to be adventurous and take risks in order to get the most
from it. One or two experimental kites might ultimately not fly too well, but they
may have other qualities that make their builders equally proud of their efforts.
The other issue that Gardner raises concerns the richness of the relevant schemata. In
developing foundation studies and the associated designing activities, the opportunity
should be provided for students to make the greatest number of possible connections
to design whilst building up their capability in a particular area of technology. Kites
provide a particularly rich opportunity because of their history, cultural significance and
the nature of the associated technology – as well, of course, as the excitement and
enjoyment of getting them to fly. The following examples demonstrate some of their
potential.
Kite technology
The traditional approach to getting kites to fly has been to follow an established pattern.
Essentially, kite making has been a craft activity. Our understanding has now increased,
however, and this means other approaches are possible. Two scientists – Toshio Ito and
Hirotsugu Komura – studied kites and sought to explain why they fly (see their book
Kites: the Science and the Wonder, Japan Publications Inc., 1983). Thus it is possible to
look more closely at the scientific aspects of the technological knowledge that enables
working kites to be designed, rather than simply repeating previous successes.
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Kite materials
It is essential to achieve good ratios of strength and stiffness to weight, if the
kites are to fly. Kite materials have therefore been selected from those available
at particular times and places to fulfil the required roles. Silk, paper, bamboo,
cloth, leaves, wood and modern synthetic materials have all been used.
Identifying why and finding modern available equivalents can lead to considerable understanding of the nature of materials. The focused practical task suggests
the use of newspaper and artstraws in order to construct a kite, but the use of recycled
materials is also a posssibility. Experimenting with such materials helps to develop
technological values like practicality, ingenuity, empathy and a concern for ‘appropriateness’.
Kite design
Designing and making a kite requires the synthesis of issues from a range of areas –
cultural, historical, visual and technological. Such synthesis will require a variety of
modelling techniques, including 2-D drawings, both decorative and functional, 3-D
prototypes to test performance, and cognitive modelling in order to imagine a design.
As the design moves into the areas of structural analysis and materials selection, the
pedagogical difficulties associated with integrating design and science need to be
addressed. Designers tend to talk in terms of various kinds of modelling, whereas
scientists refer to various kinds of notation. Finding representations of scientific
principles that facilitate design modelling is not always straightforward, but visual
representations (graphs and diagrams) would be expected to help.
Visual explanations
One way of addressing the issue of visual representation, particularly bearing in
mind the age range of the pupils, is to make maximum use of clear diagrams to
explain technical ideas. Technology has been captured visually for generations,
probably since it was first captured.
Three A4 posters have been included in this pack. These could be enlarged and put
on a wall, in order to be directly available to the pupils. Visual explanations of
technology are one way of helping pupils bring design and science together.
Cross-curricular links
Cross-curricular links to the humanities and art and design have been built into the
FPT and DMA. Links to science, mathematics and ICT have been treated separately in
order to give teachers specific control of these areas. They may be suitable for some
pupils and not for others. Such cross-curricular links are one way in which teachers can
approach differentiation.
Differentiation
Differentiation has also been facilitated through the inclusion of tasks relating to investigating, disassembling and evaluating familiar products and applications (IDEAs). These
relate to two areas of the design and technology programmes of study – materials, and
components and structures. These can be used flexibly both to support those having
difficulty with particular areas and to challenge pupils to look at new areas.
Teachers need to spend as much time as possible on more challenging tasks such as differentiation. It is hoped that this pack will promote and support an independent
learning approach, which is a key aspect of design and technology.
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Structure of this pack
The pack consists of:
◆ this general introduction;
◆ teacher’s notes (TN) before each of the three sections (FPT; DMA; IDEAs and
extension tasks);
◆ 45 photocopiable student worksheets;
◆ three A4 colour information sheets (IS), which could be enlarged to make posters
if required.
Student worksheets
Section 1 (Building a kite – a focused practical task)
12 WORKSHEETS (FPT1–12)
Context: recycling
Focuses: making skills
evaluating structures
Section 2 (Kite design – a design and make assignment)
17 WORKSHEETS (DMA1–17)
Briefs: ‘kite’ briefs for different contexts
Focuses: designing skills (links to art and design)
making skills
materials and components
quality
planning
Section 3 (IDEAs and extension tasks)
16 WORKSHEETS
MC1–5: materials
and components
Activities aimed at Years 7, 8 and 9. They are suitable
for either initial teaching or extension activities.
S1–3: structures
Activities aimed at Years 7, 8 and 9. Again, they are
suitable for either initial teaching or extension
activities.
Cross-curricular links:
Sc1–4: science
Understanding the atmosphere, measuring forces, understanding gravity, lift and drag forces.
M1–2: mathematics
Measuring distances, angles and heights, scaling lengths
and enlargements.
ICT1–2: information and
communication technology
Use of the Internet (kites, recycling, etc.), graphics packages,
CAD/CAM (stick-on plastic images, embroidery).
Information sheets
These sheets divide the text, but it is also possible to enlarge them so they serve as wall
charts/posters. The first of these posters tries to indicate the general strategy for
constructing the original kite shown in the FPT, so that pupils can be given an overview
of the kite-making process. The second poster shows some interesting modern designs
which relate to the design briefs given in the pack. It might be used to provide inspiration
if necessary. The third poster relates particularly to materials for kite making in different
times and cultures. It also indicates the key features of kite forms and how they have
evolved.
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Programmes of study
It is anticipated that teachers will use the pack flexibly and place appropriate
emphases in order to provide the required balance in the school’s Key Stage 3
curriculum. The table below, however, indicates those aspects of the KS3
programmes of study that could potentially be addressed through this resource
pack, along with relevant worksheets. The time available for the project will be the
major factor in determining which aspects are covered.
Aspects of programmes of study
DMAs: resistant materials
compliant materials
and/or food
FPTs
IDEAs
√
√
×
√
√
DMA1–17
DMA 1–17
work independently/in teams
apply programmes of study of other
subjects
√
√
DMA16
Sc1–4, M1–2,
ICT1–2
Designing skills
Identify sources
Use design briefs
Develop specification
Consider needs and values
Generate and modify proposals
Consider aesthetics, function
Take account of properties of materials
Prioritise and reconcile decisions
Take account of restrictions
Model ideas
Develop plan and alternatives
Evaluate design ideas
√
√
√
√
√
√
√
√
√
√
√
√
ICT1, DMA9
DMA4
DMA5
DMA1, DMA4
DMA6–7
DMA6–7
DMA2–3
DMA13
DMA12–13
DMA6, DMA12
DMA15
DMA13
Making skills
Use forming processes
Select tools/process materials
Use appropriate methods of shaping
Join/combine materials and components
Use construction kits
Interconnect a variety of components
Apply finishing techniques
Make products in quantity
Develop strategies for making
Evaluate/test products
Implement identified improvements
√
√
√
√
×
√
√
√
√
√
√
DMA12
DMA12
DMA12
DMA11
Properties of materials
Classification of materials
Combining, processing, finishing materials
Heat treatment and combining materials
Pressing/casting materials
√
√
√
×
×
MC2–3
DMA9
DMA10–11, MC4
Opportunities for
capability through:
Opportunities to:
Materials and
components
©
Covered Relevant
in pack? worksheets
FPT1–10
MC1–5, S1–3
DMA11
DMA10
DMA16
DMA14–15
FPT8–11, DMA17
FPT12, DMA12
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Aspects of programmes of study
Covered Relevant
in pack? worksheets
Systems and
control
Design, use, interconnect
Mechanisms and movement
Use switches to control devices
Use sensors
Systems have inputs, process, outputs
Feedback
Analyse performance of systems
×
√
×
×
×
×
×
Structures
Recognise and use structures
Failure of structures
Test for excessive loads
Reinforcement methods
Understand forces and their effects
√
√
√
√
√
S1–2
DMA12
S3
MC1
Sc2–4
Products and
applications
Intended purpose
Choice of materials/components
Processes used
Scientific principles
√
√
√
DMA1
FPT2, DMA2–3
DMA3
DMA1, FPT1,
Sc2–4
Views of users and manufacturers
Alternative products
×
×
Quality
Meets need
Fitness for purpose
Use of resources
Impact beyond purpose
√
√
√
×
DMA13, DMA17
DMA13–17
DMA1–3
Health and safety
Recognise hazards
Information to assess risks
Action to control risks
√
√
√
FPT9
FPT9
FPT9
√
MC5
The SCAA document Key Stage 3 Design and Technology — The New Requirements makes
the following suggestions concerning how teachers can support pupils in their
designing. They should:
◆
◆
◆
◆
◆
◆
ask appropriate questions;
encourage pupils to discuss and explore their ideas;
encourage pupils to reflect on their work at various points in the process;
help pupils draw on skills and knowledge drawn from other subjects, particularly art;
display aspects of designing as a process, as well as finished products;
provide pupils with the opportunity to find out about designing in other contexts,
e.g. through developing links with local industry and designers.
(p. 11)
It is clear that this resource pack provides the necessary opportunities to achieve the first
five of these objectives. The last objective would require further organisation, but is
imaginable within the context of a kites project.
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In relation to making skills, the SCAA document suggests that teachers
should help pupils to consider:
◆ the physical and chemical properties of materials, and relate these
properties to the ways in which materials are worked and used;
◆ that materials can be classified according to their properties and behaviour
and to the major classifications with the material categories they are using,
e.g. thermoplastics and thermosets;
◆ that materials can be combined, processed and finished in order to create more
useful properties and desired effects, e.g. combining different ingredients to
create products with different sensory characteristics;
◆ how knowledge and skills drawn from art, mathematics and science can be applied
to making;
◆ how to relate previous experiences to new problems so that pupils develop their
ability to draw on their repertoire of skills and understanding.
(p. 15)
Of course other projects, such as the use of food and polymers, are the intended
route for meeting some of these objectives, but the potential of a project that
involves designing and making kites is evident.
Materials
The following is a list of possible sources of reclaimed materials that could be
used to make the kites.
Material
Purpose
bin bags
builders’ plastic
sheeting
cotton handkerchiefs
carrier bags
old cagoules/
waterproofs
polystyrene tiles
stiff foam
torn sails
wrapping paper
wallpaper
newspaper
hole reinforcers
biro cases
beads
fermenting tubes
(from home-brew kits)
fish tank air tubing
plastic coated
electrical wire
cover
cover
cover
cover
cover
cover
cover
cover
cover
cover
cover
reinforcer
tail attacher
connectors
connectors
connectors
connectors
Material
ribbon
paper cups
plastic cartons
plastic bottles
drinking straws
bamboo
coat hangers
kebab or barbecue
sticks
garden sticks for
potted plants
plastic tubes (rigid)
plastic knitting needles
twigs (willow is best)
reeds
fishing reel line
sewing thread
cotton reels
drinks cans
food trays (polystyrene)
Purpose
connectors/tail
tail decoration
tail decoration
tail decoration
struts/springs/
tail attacher
struts
struts
struts
struts
struts
struts
struts
struts
line/bridle
line/connectors
reel
reel
reel
Artstraws, dowelling and ‘structa sticks’ can be purchased cheaply and are very
effective materials for struts.
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Tools and equipment
The following items are typical of those that need to be available:
◆
◆
◆
◆
◆
◆
◆
sellotape
coping saws
cutting mats
glue
hot glue gun
paint
spray mount
◆
◆
◆
◆
◆
◆
◆
pairs of compasses
cutting knives
felt tips
hand drills
masking tape
scissors
vices
Contacts and other resources
The Internet
The Internet is a very powerful resource for use with this project, both for pupils and
teachers. The Kite Society of Great Britain Web site (http://ourworld.compuserve.com/
homepages/kite_society/) provides an up-to-date list of shops, wholesalers, retailers,
festival traders, manufacturers and mail order companies, as well as indicating whether
books, magazines, kite-making materials, etc. are stocked. These are shown by area and
it would be the best way to locate useful contacts near to you. The first page of this Web
site has been reproduced on ICT1 (p.70); the postal address of the Kite Society of
Great Britain is shown overleaf in case you do not have access to the Internet.
There are other sites containing a wealth of information concerning the art, history,
science, technology and practice of building and flying kites, as well as details of
organisations, publications and events. Some sites contain details of music relating
to kites, stories and safety rules for flying. It is well worth making the effort to find
a way of obtaining Internet access. The best Web sites relating to kites are as
follows:
The American Kitefliers Association: http://www.aka.kite.org/
The Australian Kiteflyers Society: http://www.aks.org.au/
The Drachen Foundation: http://www.drachen.org/
Exeter Kite Central: http://info.ex.ac.uk/~jastaple/kites/html
Kite Fliers Site: http://www.kfs.org/kites/
The Kite Society of Great Britain (see above)
Kites.Org: http://www.kites.org/
The Midlands Kite Fliers of Great Britain:
http://www.canleo.demon.co.uk/mkf/welcome.htm
◆ Peter’s Kite Site: http://www.win.tue.nl/cs/fm/pp/kites/index.html
◆
◆
◆
◆
◆
◆
◆
◆
Books
Bridgewater, A. and G. (1985) Easy to Make Decorative Kites, Dover Publications Inc.
Eden, M. (1989) Kiteworks: Explorations in Kite Building and Flying, Sterling Publishing
Company Inc.
Hart, C. (1982) Kites: An Historical Survey, Paul P. Appel.
Ito, T. and Komura, H. (1983) Kites: the Science and the Wonder, Japan Publications Inc.
Kent, S. (1997) The Creative Book of Kites, CLB International.
Moulton, R. (1978) Kites, Pelham Books.
Pelham, D. (1976) The Penguin Book of Kites, Penguin.
Streeter, T. (1980) The Art of the Japanese Kite, Weatherhill.
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American Kite
P O Box 699
Cedar Ridge
CA 95924
USA
Tel.: 916-273-3855
Fax: 916-273-3319
Kites
17 Crowborough Road
Saltdean
East Sussex
BN2 8EA
Tel./fax: 01273-308787
Kite Passion
P O Box 152
Woking
GU21 1FS
Tel.: 01795-414849
The Kiteflier
(newsletter of
the Kite Society
of Great Britain)
P O Box 2274
Gt Horkesley
Colchester
Essex
CO6 4AY
Tel./fax: 01206-271489
Kite Lines
P O Box 466
Randallstown
MD 21133-9987
USA
Tel.: 410-922-1212
Fax: 410-922-4262
e-mail: [email protected]
Magazines
For an extensive, up-to-date list of books and magazines, see the Peter’s Kite
Site Web pages (address above).
Acknowledgements
We would like to thank Dr Howard Denton (Programme Leader for the Industrial
Design and Technology degree at Loughborough University) and Georgina Royle
(Head of Design and Technology at St Paul’s RC Comprehensive School, Leicester)
for their helpful comments and criticisms concerning early drafts.
Thanks also to Nicola Heyes for her work as a Research Assistant on this resource
pack, the preparation of which was substantially funded by the Department of Design
and Technology at Loughborough University.
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SECTION 1
Construction of a ‘paper
and artstraw’ original kite
is
Main stiffeners
Smaller ribs
Stiffened
area
Spring
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SECTION 1
Building a kite –
a focused practical task
tn
he general aim of this focused practical task (FPT) is to motivate the pupils
by putting them in the position of the early kite builders and taking them
through a first kite-building experience in a controlled way. Clearly it is to be
hoped that the kites fly well, but there are a great many minor objectives to be met
prior to the ‘flight tests’. For example, developing an understanding of:
◆
◆
◆
◆
◆
◆
◆
◆
◆
◆
◆
the requisite shape of kites (FPT1);
kite materials and their required properties (FPT2);
natural forms by looking at nature for inspiration (FPT3);
the role of stiffeners (FPT4);
compression forces (struts) and a feel for the forces involved in kite flying (FPT5);
the concept of centre of gravity (FPT6);
tension forces (ties) (FPT7);
stability (FPT8 and FPT10);
safety issues relating to kite flying (FPT9);
how to fly a kite (FPT11);
how to analyse and improve a design (FPT12).
Pupils may be more or less aware of these concepts from previous studies and,
consequently, the time allocated and the balance of the activities must be
determined by the teacher to suit their circumstances. The following notes relate to
the possibilities afforded by each worksheet; the relevance in a particular school’s
curriculum cannot be predetermined. The notes are intended to help teachers to
make the most of the opportunities.
The analysis presented here is a very simplified version of that developed by two
scientists, Drs Toshio Ito and Hirotsugu Komura. They experimented for 4 years
with over 1,000 model kites and presented their findings in a book, Kites: the Science
and the Wonder (Japan Publications Inc., 1983). The book is too complex for KS3
pupils, but would nevertheless make a useful addition to the school library for teachers
and older pupils. It is hoped that this FPT will provide a richer educational experience
than the ‘paperfold’ kites, which can be found in David Pelham’s The Penguin Book of
Kites, and the ‘trash-bag sled’, which can be found in Sara Kent’s The Creative Book of Kites.
However, both of these would be quicker for the pupils to make and get them into kite
flying more rapidly.
Notes on worksheets FPT1–12
FPT1 The shape of a kite
Kites come in a vast range of shapes and sizes, which is part of their fascination. The
worksheet should help pupils to realise that there are two key features that can be
identified on all kites: (a) a ‘wind-receiving plane’; and (b) some surface area perpendicular to the wind-receiving plane.
A wind-receiving plane does exactly that – it receives the wind and provides the lift.
However, a kite consisting solely of a flat surface would be unstable, so it is necessary to
have some surface area perpendicular to it in order to provide lateral stability. A keel is one
way of arranging this, but there are other possibilities. A curved surface has some vertical
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height (it is not flat if looked at from the side) and can have an equivalent
effect. This is the reason for the curved shape of the classic ‘bowed eddy’ kite.
It is possible to look at all kinds of kite shapes and identify these two key
features.
tn
FPT2 Choosing materials for your kite
How much the pupils know about different materials and their properties will
vary, but the worksheet provides an opportunity to discuss this subject. It would be
advisable either to have collected materials in advance and ask pupils to choose
those that are suitable for different parts of the kite – or to set them the task of
bringing some in to discuss. It is also an opportunity to discuss the making of kites
from materials reclaimed from the immediate environment (e.g. dustbin liners, fishing
line, newspapers/magazines, etc.) This is an informal way of developing children’s
understanding of material properties and the requirements for different situations. (This
concept can be developed more formally through the IDEAs worksheets on materials
and structures.) The extension task on the worksheet continues the development of an
understanding of kite shapes by analogy with yachts and catamarans. Lateral stability
can be achieved by a pair of hulls as well as a keel.
FPT3 Making the kite body
The first kite builders looked towards birds and other flying creatures in order to help
them understand how things fly; this is therefore a natural step to ask children to
take. This particular worksheet asks them to look at butterflies and provides the
opportunity for pupils to be given a lesson on observing nature and drawing what
they see. Examples could be drawn from the work of numerous artists, but
Leonardo da Vinci is a good artist to study. All the pupils need is rough paper, some
old Sunday supplement magazines, newspapers or plastic carrier bags, and scissors
to cut out their butterfly shapes. Some books or slides showing pictures of various
butterflies would be a useful addition in the classroom.
FPT4 Stiffening the wings
This worksheet continues the theme of observing nature. The veins in a butterfly’s
wing stiffen the wing when pumped full of blood, and this give the wings the
strength that enables the butterfly to fly. The illustrations show the principles
developed by Ito and Komura for stiffening a wing made of flat material. An
inexpensive way for the pupils to experience the process of stiffening is for them to
stick double and single artstraws onto a paper shape (from FPT3). As the straws are
stuck on, the stiffening effect is remarkable; this forms a valuable lesson for the pupils.
Of course, many kite designs use fabric or flexible materials in tension rather than stiff
wing sections, but one of the significant attractions of starting with the above approach
is the experience the pupils will have in glueing on the stiffeners. It is better to use an
adhesive that dries reasonably quickly, so that the pupils can create their design quickly,
and in easy stages. The effect is thus more obvious than if they have to wait until next
lesson for the adhesive to have dried fully on all the stiffeners.
FPT5 Springing the wings
From the point of view of its use in the classroom, this is probably both the greatest
strength and the greatest weakness of the kite design approach developed by Ito and
Komura. Some craft skill is required to glue the spring in position but the great benefits
are that you can fly the kite with ordinary cotton (because the kite collapses when the
wind force gets too high) and the pupils can thereby get a feel for the force created by
the wind. They will know that quite a high force is required to compress the spring but
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they will see the kite folding when it flies and the wind gusts. Ito and Komura
recommended using piano wire for the spring, but the ends can be rather
sharp. A plastic drinking straw (the small-diameter type used in cartons) seems
to work just as well as piano wire and the pupils can be asked to bring some
to the class. The straws can be joined by pushing them together and, if
necessary, secured with a glue gun.
tn
The spring is a member in compression – a strut – and this is a good introduction
to the behaviour of struts when they are subjected to loads sufficient to make them
buckle. If pupils get into difficulties fitting the spring, a solid (wooden) strut could
be fitted instead – although the wings will not then, of course, flap when the kite is
flown. (The dihedral angle should be set at 5–10° – see worksheet FPT10.) The force
generated by a high gust of wind may also break an ordinary cotton line if the strut is
too solid.
This spring is performing a similar function to the cross-member in a delta kite (see
DMA3) – although the delta kite is the other way up. It would be useful to demonstrate
this if one happens to be available (one of the pupils might own one). More able pupils
might be encouraged to research and explain the operation of the Indian fighting kite,
which has a bamboo spring.
FPT6 How to balance the kite
The towing line must be attached so that when pulled it acts above the centre of
gravity if the kite is to fly. (This is illustrated in the science extension worksheets
Sc2–4.) The FPT6 worksheet introduces students to the concept of the centre of
gravity and how to find it. Once they have grasped the idea of balance around the
centre of gravity they will have begun to understand stability. In discussing the
concept of stability it may be useful to draw attention to work done in science
lessons on human balance and the workings of the inner ear in detecting yaw, roll
and pitch.
FPT7 Attaching the line
Attaching the line to the kite is the first preparation for flying. This worksheet
illustrates simple ways of creating a bridle point, which is easily adjusted using a
RED connection (named after Red Braswell, a kite designer). It also shows how a reel
can be made from an old drinks can.
FPT8 Preparing to test your kite
There is a need for pupils to record in detail their first attempts at flying their kite, and
then to try to analyse any problems that occurred. This worksheet prepares the way for
this process and should be used in conjunction with FPT9–11. The pupils should decide
on any modifications to the design that may be needed, retest the kites and record the
eventual results. They might be asked to carry out the tests and complete FPT8 for
homework after suitable preparations have been made in class (using FPT9 and 10).
FPT9 Safety
Clearly, before any flying takes place it will be necessary to consider safety issues.
Lightning, cliffs, trees, electricity pylons and airports all present their own hazards. It will
be useful to have a general discussion concerning safety hazards when flying kites and
then to bring to the pupils’ attention any known local issues. Kites can interfere with radar
signals, which is why they should not be flown within 5 kilometres of an airport. Legally
kites must also fly below 200 feet (c.60 metres).
Large kites can generate correspondingly large forces, therefore there is a risk of string
burns, etc., when manipulating the line. Large kites require careful attention to be paid
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to the design of suitable line-winding mechanisms. The kites being made in the
FPT are small, and cotton rather than nylon is being used for the flying line.
Such risks are therefore minimal.
tn
FPT10 Improving stability – stopping the wobble
Without a tail or fin, the kite is likely to fly in a very unstable way. The pupils
should try this to see what happens, but at some point in the flight trials it will
prove necessary to add either a tail fin or a tail. This worksheet explains how. The
pupils could be asked to test the kites for homework and to add a tail fin and, if
necessary, a tail. They could then report back on their successes and failures in flying
the paper kites.
FPT11 First flights
Worksheet FPT10 should give enough information for the students to troubleshoot early
flying difficulties. If the first flights are taking place on the school field, it will be useful
if they are organised. It is helpful to establish the wind direction and spread the students
out – perhaps in four or five groups – parallel to the wind. They should be able to take
turns in flying their kites without tangling the lines. The students watching will gain
useful information for their evaluations from taking notes on what happens to their
friends’ kites.
The paper kites are likely to be damaged during these trials, but should last long
enough for the students to gain some flying experience. Artstraws tend to fold when
too high a load is applied, which allows the wing to fold. The kite will then not fly
properly. Such damage provides a very useful starting point for discussions on
structures: what is good about artstraws? What stronger material could replace
them? Bamboo is commonly used for struts and it would be useful at this stage to
discuss its properties. Very thin bamboo could be used with paper kites, but thin
sections of wood (or veneer) are equally possible. What shape should these be? It
is useful to have scissors and sellotape available when the paper kites are being
flown, in order to make initial running repairs.
FPT12 Final evaluation
This worksheet is provided to enable pupils to record their analysis of the problems,
the changes they made and whether or not these changes led to an improvement in
their kite’s performance. With a little time spent in the classroom it should be
possible for the damage from the first flights to be repaired and the kites returned to
a good enough condition to allow them to be retested. Repairs with sellotape and/or
strips of paper and glue should be strong enough.
The extension task, concerning the investigation of the effects of changing the (fixed)
dihedral angle on the kites’ stability, has been included to stretch the most able. The
spring will need to be removed and replaced by fixed struts of increasing length. The tests
could be carried out with and without a tail fin and with and without a tail.
Leading towards the DMA
The experience of making and testing a kite made from paper and artstraws should have
helped the pupils start to get to grips with structural and kite technology. It is not intended
to be an end in itself, but to provide a rich learning experience at low cost. If the primary
requirement, however, is to cover the ‘structures’ element of the National Curriculum, it
could provide sufficiently for this. There are elements of designing involved, and it
provides enough opportunities with appropriate materials and structures extension tasks
to cover the NC requirements. It is, however, the DMA that should provide the real
design experience.
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FPT
1
focused practical task
The shape of a kite
flexi ble
st ructures
SECTION 1
These diagrams show the two classic kite shapes. They show us the important
features that determine how a kite flies. Kites need to have:
◆ a large area that catches the wind. This is called the ‘body’, ‘cover’ or ‘wind-
receiving plane’;
◆ an area that helps to control it when riding the wind. The kite will then keep
its position rather than sliding away with the wind.
The area that helps the kite to ride the wind can be formed in either of two
ways:
◆ by making a keel, like a keel on a boat. This forms a piece at right angles to
the main kite area;
◆ by giving the kite a flexible body so that it curves with the wind and is threedimensional (3-D).
Spar
Bow string
View of the frame
Bowed
Eddy
Bridle
Spine
Control line
Tail
Delta
TA S K 1
(a) Identify the wind-receiving plane on both of the kites shown.
(b) Identify the keel on one of these kites.
(c) Find the kite that has no keel and identify the area that helps it to keep
its position in the wind.
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FPT
2
focused practical task
flexi ble
st ructures
SECTION 1
Choosing materials
for your kite
Kites have a number of key parts, some of which you have seen on FPT1. These are:
◆
◆
◆
◆
◆
the line;
the wind-receiving plane, body or cover;
the keel;
stiffening ribs to keep the right shape;
connectors to join all the parts.
Traditionally, many different people have made kites; the style and materials that
they used reflected their country and culture. You can make use of reclaimed
materials that you might find at home or at school to make your kite. Before
you start you need to have a clear idea of the structure of your kite. Then think
about the materials that might be suitable for each part of the structure. A good
way of doing this is to brainstorm the problem and put the ideas that you come
up with onto a diagram:
Plant canes
Plastic tubing
CONNECTORS
Box kite
STIFFENING RIBS
Fishing line
BODY
LINE
Dustbin liners
TA S K 2
We have started to brainstorm a kite design and record our
ideas on the diagram above. Look at any posters in your classroom showing different kinds of kites. You may also have
books or computer-based resources to help you.
(a) Choose a kite design and draw a sketch of it in a big box in
the centre of a new page.
(b) Identify the parts that you would need for your chosen kite
design and draw them in spaces around the central sketch
in a similar way to the one shown above.
(c) Decide which materials you could either buy cheaply or
recycle for each part of your design.
(d) Now match up a suitable material with each part of your
kite design. Show them clearly on your diagram, perhaps
by colouring in the ones that you have chosen.
©
Key Stage 3 Design and Technology Resource Pack
Extension task
The kite that we
have sketched is a
box kite. Its
stability comes
from being like a
catamaran. Find
pictures of a yacht
and a catamaran
and compare their
shapes. Can you
work out why they
are stable? (This is
quite a difficult
question!)
17
FPT
3
focused practical task
Making the kite body
flexi ble
st ructures
SECTION 1
Kites have been made in many different
countries for thousands of years and have
fascinated a great number of people. Let’s build
one of our own and try it out. Some insects –
such as the butterfly – have fixed wings, so they
make an ideal form for our kite design. We shall
build a kite based on the butterfly, with two fixed wings.
These wings are able to flap
gently in the wind.
A kite design based on Kites: the Science and
the Wonder by Toshio Ito and Hirotsugu Komura.
TA S K 3
Fold
(a) Practise drawing a butterfly shape on rough paper until you are happy with the
shape.
(b) Your kite fabric will be paper. Open out a double sheet of paper from a newspaper or magazine. These are about the right size for you to draw your butterfly.
The area of your kite should be between 1,000 and 2,000 cm2.
(c) Fold your paper down the middle.
Mark a point 7 cm from the top of
Leading edge 3
the rectangle and another point
2
7 cm
25 cm below this. These two points
represent the length of the centre
1 on the diagram
spine. (See ●
opposite.)
2
(d) Draw a small arc to represent the
3
25 cm
1
butterfly’s head, near the top marked
2
point. ●
4
(e) Draw a large forward arc for the
3
leading edge. ●
(f) Draw a shallower curve to about two
1
4
thirds of the height. ●
3
(g) Draw a lower curve to intersect with
the previous one. This forms the
5
bottom part of the wing. ●
5
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FPT
4
focused practical task
flexi ble
st ructures
SECTION 1
Stiffening the wings
Before we can fly the kite the wings need to be made rigid. Just as the veins on
the butterfly’s wings give them rigidity, we need to attach stiffening ribs. There
are three areas of stiffening:
◆ The forward edge of the kite is also called the leading edge. This must hold its
shape in the wind, no matter how strong the wind is, so it needs to be
stiffened with several small ribs.
◆ The back edge is also known as the trailing edge. This does not need to be so
stiff, as the wind flows over it more easily. A smaller number of light ribs will
do here.
◆ The main area of the kite needs to be very stiff; this is done with stronger ribs.
The diagram opposite shows you how to stiffen your kite wing.
Leading edge
◆ The solid lines represent heavy
ribs, which create the windreceiving plane (shown shaded).
◆ The dotted lines represent
thinner stiffening ribs, which
can be used to keep the weight
down.
Figure 2
Trailing edge
Heavy
ribs
Lighter
ribs
Windreceiving
plane
Figure 1
Figures 1–3 show the principle of stiffening
the wings, in this case, using single and double
artstraws for the heavy and lighter ribs.
Figure 3
TA S K 4
(a) Choose a strong, light material for the
heavy ribs and stick them to the butterfly shape you have cut out, as shown.
You will need to join the ribs where
they cross. The photographs show
you how this can be done.
(b) Find materials you think will be
suitable for the small ribs and stick
them to the edges of the butterfly
wing, to stiffen it.
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FPT
5
focused practical task
Springing the wings
flexi ble
st ructures
SECTION 1
By now you should have two stiffened wings that flap. In order for the kite to
fly, however, you must make sure that the wings cannot close. This is done with
a strut, which acts like a spring (see the photos below). The strut is held between
two holders. It is a little bit shorter than the distance between the holders and is
pushed against the ribs to stop the wings closing together. The wings should be
set at a small angle of between 5° and 10°. If the wind blows too strongly the
strut will collapse; this stops your line breaking.
The ends of the strut can be held in cut paper artstraws, which need to be glued
to the thick ribs. The spring can be glued in directly or else wrapped in paper, in
order to provide a more secure fit.
Cut the paper
artstraw
or wrap in
paper first
1–2 cm
TA S K 5
Attach a length of stiff, springy plastic tubing
or wire (e.g. piano wire of about 1 mm diameter) to hold the two wings in a flying
position. Two plastic drinking straws fixed
together will also work well, as shown here.
Extension task
If you think that you may want to fold your kite to carry it, design a safe fixing
that you can release to fold it flat.
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FPT
6
focused practical task
flexi ble
st ructures
SECTION 1
How to balance
the kite
Every object has a point of balance where all of its weight appears to act. This
point is called the centre of gravity. Can you guess where the centre of gravity of
some objects – like a ruler or a pair of scissors or a book – might be? We can
find where the centre of gravity is for any object.
TA S K 6
(a) Finding the centre of gravity of a ruler
Place your hand under the mid-point of a ruler so
that it balances on one finger. You are supporting
all the ruler’s weight at this point and your finger
is directly under the centre of gravity.
A
(b) Finding the centre of gravity of a different shape
◆ Cut a triangle or other shape out of card. Now that we
have a 2-D shape it is harder to find its centre of gravity.
◆ Pin the shape to a board with a drawing pin close
to one corner.
◆ Hang a heavy weight by a string so that it hangs
C
B
◆ Mark where the string crosses the bottom edge of
C
Line
previously
drawn
freely from the drawing pin. (This is known as a
plumb line.)
the shape. Then draw a line to join this point to
Where
the lines
the top corner.
cross is
the centre◆ Now hang the shape up by another corner and
of gravity
mark a new vertical line.
◆ Where the two lines cross is the centre of gravity.
A
B
If you marked a third vertical line it would go
through the same point.
(c) Finding the centre of gravity of your
butterfly wings
The centre of gravity of the butterfly wings will be
down the centre fold because the butterfly is a
symmetrical shape. Hang it up by a wing tip and mark
where the vertical line crosses the centre fold. This is the
point at which the weight of the butterfly appears to act.
©
Key Stage 3 Design and Technology Resource Pack
Centre of
gravity
21
FPT
7
focused practical task
Attaching the line
flexi ble
st ructures
SECTION 1
The kite is expected to fly with the spine at an angle of 10–15° to the horizontal.
This can only be achieved if the control line is attached to a point on the bridle,
so that when pulled it acts in front of the centre of gravity (i.e. between the
leading edge of your kite and the centre of gravity). We must now attach the line
in the right place on the central spine so that it is supported at this angle.
Control
line ‘pulled’
in flight
Bridle line
Bridle
Washer
3 cm
Centre of
gravity
3 cm
Control line acts
in front of the
centre of gravity
RED connection
loop (named after
Red Braswell,
a kite designer),
also known as a
larkshead hitch
Put the ring through
the loop to make a
connection that is
easily adjusted
along the bridle
10–15°
TA S K 7
(a) Choose a material for your kite line. (Cotton should be strong enough for a
sprung kite.)
(b) Tie the bridle line to the kite’s main frame about 3 cm from each end of the
main spine.
(c) Make a RED connection
using a small washer, as
shown in the diagram.
(d) Tie the control line to the
washer.
(e) Wrap the other end of the
line around an old drinks
can and secure the other
end to the ring pull.
(f) Adjust your kite so that it
hangs at about 10–15°.
Your kite is now nearly
ready to fly.
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focused practical task
FPT
Preparing to test
your kite
8
flexi ble
st ructures
SECTION 1
When you first try to fly your kite many different things can go wrong. If you
keep a careful record of what happens it will help you to understand any
problems that may arise. Then you can discuss with your teacher things you
might do to improve the kite. It is also better to change only one thing at
a time, as you will probably already have learnt in your science lessons! This
worksheet is for you to record what happens when you test your original kite
and then when you add a tail fin and a tail. Before you test your kite, however,
you must think about safety (worksheet FPT9) and learn how to make tail fins
and tails (worksheet FPT10).
TA S K 8
Test
Sketch
Flight report
Comments
No tail
With
tail fin
With tail
fin and
tail
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FPT
9
focused practical task
Safety
flexi ble
st ructures
SECTION 1
Flying kites might not seem dangerous,
but there are a number of ways accidents
can happen.
TA S K 9
(a) Look at the diagrams on
this worksheet, and think
about possible dangers
when you fly a kite.
(b) List some accidents that
could happen when you
fly a kite.
(c) Decide how you are going
to make sure that you will
be a safe kite pilot.
©
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focused practical task
FPT
10
Improving stability –
stopping the wobble
Without a tail fin or tail your kite is
likely to rotate, wobble and dive as
well as slide down to the ground.
This means that it is unstable and
there are many different ways that
your kite can crash! Attaching the
line as we did, in front of the centre
of gravity, will help to make it more
stable. The kite already has its wings
at a small angle (known as a dihedral
angle), which gives some stability.
flexi ble
st ructures
SECTION 1
Dihedral angle (5–10°)
If we add an area of vertical
material it will help to improve
the stability of your kite. This is
known as a vertical tail fin.
Under some conditions you
might also need to add a tail
with bows made from cotton,
ribbons or paper tape to stabilise
it further, so be prepared when
you test your kite.
The force of the wind on
the tail stops the kite
rotating forwards
TA S K 1 0
(a) Think of a shape for your kite tail fin and cut out two
identical pieces. (A circle with a radius of 6 cm or a square with 5
cm sides will be about the right size.)
(b) Use light kebab sticks or connect plastic drinking straws together if
necessary, to make a length of about 20 cm and cut another to be the
same height as your tail fin.
(c) Glue these as shown between the pieces that you have cut for the tail fin. The
longer stick will be attached to the main central spar of the butterfly and the
shorter one will be at right angles to it. (Thin, stiff wire can be used as a good
alternative material for the fin stiffeners, but be careful of the sharp ends.)
(d) Make a tail which you can attach to your kite.
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FPT
11
focused practical task
flexi ble
st ructures
SECTION 1
First flights
It is now time to have a go
at flying your kite.
TA S K 1 1
Fly your kite on a short line with no tail, with a tail fin and with a tail and record your
results on worksheet FPT8. Then study the information given below and see if you can
work out the solution to any difficulties you have found.
Troubleshooting
The most likely difficulty that you will have (apart from the wind) is the position of
the bridle (or towing) point where the line attaches to the kite.
◆ If the kite spins and crashes forward, move the bridle point towards the centre.
If this point is too low, however, the kite will not fly.
‘Crashing’
forward
Poor lift
◆ In a light breeze you should move the bridle point forward. This makes the kite
◆
◆
◆
◆
◆
©
fly more easily and also higher, but you may need a vertical tail fin if you have
not already got one.
In a heavy wind the bridle should be moved back.
If the kite is still unstable, check that the wind-receiving plane is flat, that the frame
is not bent and that there are no wrinkles in the paper.
If the kite flies with one wing higher than the other, attach a piece of tape
(or something similar) to the higher side.
If the kite flies forward and then dives, check that the leading edge is flat and
undamaged or make the ribs on the trailing edge lighter.
If you still have problems, add a tail. This should stop the kite diving.
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focused practical task
FPT
12
Final evaluation
flexi ble
st ructures
SECTION 1
TA S K 1 2
This worksheet should help you to evaluate the kite you have made.
Results of the first flight tests
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
Problems encountered
Suggested reasons for problems
...................................................................
................................................................
...................................................................
................................................................
...................................................................
................................................................
...................................................................
................................................................
...................................................................
................................................................
...................................................................
................................................................
...................................................................
................................................................
...................................................................
................................................................
Changes made
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
Results of the next flight tests
.......................................................................................................................................
.......................................................................................................................................
.......................................................................................................................................
Extension task
If you have finished everything else then there is one final set of tests you can
do. The spring can be replaced with a solid spar so that it does not buckle. Of
course the cotton may now break, but it is possible to investigate the effect of
changing the dihedral angle (see worksheet FPT10). You will need to start with a
long spar and measure the dihedral angle. Fly the kite to see what happens and
then try shortening the spar, so that the dihedral angle increases. How does the
behaviour of the kite change?
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SECTION 2
©
Some interesting
kite designs
Key Stage 3 Design and Technology Resource Pack
2
is
28
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SECTION 2
Kite design –
a design and make
assignment
2
tn
he 17 worksheets in this section provide a loose framework for the management
of the design and make assignment (DMA). Designing should be as open an
experience as possible, drawing on any available resources in any way that helps.
The Internet, local kite clubs and shops, visiting enthusiasts, books and magazines may
all have major roles to play. In the end, the fact that appropriate activities are being
carried out by the students is more important than the order in which things get done.
All teachers will, no doubt, have their own preferred way of monitoring the progress of
their pupils as their design directions diverge, but the photocopiable chart on p. 33 has
been included as one possibility.
Notes on worksheets DMA1–17
DMA1– 3 Different designs and materials
These three worksheets are intended to open the pupils’ minds to the wide range of
ways in which kites have been used and the different materials from which they
have been made through the ages. The materials used are related to the local
environment, time period and culture, and studying the purposes for which the
kites have been designed and the associated materials provides potential links with
the humanities curriculum.
The key aim of these worksheets, however, is to ensure that the pupils do not think
that there is only one way forward (if they have completed a paper kite as a focused
practical task). It is important to emphasise that they can and should take any
appropriate route. Worksheets DMA2 and 3 show the more recent materials to have
been used and the associated design developments. Many of the designs depend on
the ability of textile and polymer materials to carry large wind loads without tearing.
It would be possible to draw parallels with the development of sails, parachutes, tents
and similar items. Teachers may at this point want to use worksheet MC1, concerning
bag and tent construction, as either a homework or an extension task.
DMA 4–5 Design briefs and specifications
Some possible design briefs are shown on DMA4. Clearly there are many other possibilities, but these briefs will provide a starting point. Writing a detailed specification of all
the things that the kite must be able to do is a difficult task, and worksheet DMA5
contains some suggestions and various matters that need to be taken into account. The
pupils will probably just want to start designing, but it is important that they establish a
direction in which to head. Setting this clear target helps provide a basis for the
judgements they will have to make when carrying out their design.
DMA6 Designing a shape
The pupils may well have a clear idea of the shape that they would like their kite to be.
Helping them to realise this objective, rather than having them make a kite that is
known to fly well from previous experience, is one of the key principles behind this
resource pack. This is one element of the activity that delineates it as ‘designing’.
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Alternatively, kite making could be approached entirely legitimately, and
possibly more successfully (in terms of flying prowess), as a ‘craft’ activity. It
would be possible to take the pupils through the stages required to make a kite
whose design has been well established. There are numerous books with stepby-step instructions. The pupils could even be encouraged to pursue such a
task as well as flying commercial designs. The class might be asked to bring in
as many kites as they can and time could be spent analysing their construction
and flying performance. Utilising craft-based knowledge is just as valuable as
using knowledge derived from science, but it is to be hoped that the endpoint of
such activities would be that the pupils are inspired to be adventurous rather than
conformist.
tn
It is possible that some students will want to begin their project by looking to nature
(as encouraged in worksheets FPT3 and 4). They may find a small diagram of a bird,
insect or other animal that they wish to enlarge. Worksheet M1 has been included to
help with such tasks. Having established a direction, some of the first judgements have
to be made. The shape must be symmetrical in order to be stable; if the pupil wishes
to pursue a very difficult shape from this point of view, perhaps they can make a ‘pair’
(e.g. a pair of trainers).
The materials from which the kite is made have to be chosen in relation to its size.
Very small kites have to be made from light materials such as balsa wood and
clingfilm. It is also important that the towing line is attached in front of the centre of
gravity (see the science extension worksheets Sc2–4), so we must consider how and
to what it is to be attached.
The pupils need to look at a range of kite designs and make their own judgements.
Evaluation of their first models will soon tell them how accurate their decisions
were, and they can always change them for Mark II! The students might need to be
encouraged to overcome their fear of being wrong and simply to set out along a
path to find out.
DMA7–8 Original kites
These two worksheets show a very brief version of the method recommended by Ito
and Komura for making kites of different shapes fly (see the FPT worksheets). This
might be an appropriate way forward for some of the kites the pupils wish to make.
The main stiffeners define the wind-receiving plane, but it is in the area beyond this
that there may be difficulties. The trailing edges can be shaped by the wind, but they
must not be so weak that they fold. It is important that the leading edge is stiff. Pupils
should be encouraged to experiment, using cheap or reclaimed materials. Artstraws are
recommended for the paper kite in the FPT, but more resistant materials might now be
more appropriate. Pupils pursuing this approach might well make use of worksheet S3
(testing cantilever beams) in order to reach a decision concerning a suitable material and
section. This might be an appropriate stage at which to teach them how to plane some
wood to produce a thin section. The pupils may need to be referred back to some of the
FPT worksheets.
DMA 9 Investigating kite materials
One of the requirements of NC design and technology at KS3 is that pupils should be able
to classify materials. This worksheet is intended to provide the basis for an investigation
(possibly as homework), which can be followed by a more formal discussion. Classifying
materials is not a straightforward task. The students may already have looked at the
classification of metals and non-metals in science, and care needs to be taken to build
on such work.
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Materials in design and technology tend to be classified according to their
working properties at room temperature (resistant, compliant, etc.), but
molten metals or mercury, for example, are clearly not resistant. Classifying
mercury as a metal requires a deeper understanding than simply looking at its
mechanical properties. The teacher must decide the appropriate sophistication
of the definitions of the categories of materials.
2
tn
As learning outcomes the pupils might be expected to be able give examples of a
metal, a polymer, a composite, etc. and to give some examples of ways in which
they can be distinguished. From the DMA point of view the key matter is that they
give some detailed consideration to choosing the materials they are going to use for
their kite, and that they can explain why they chose them. Part of their project
evaluation is to reflect and learn from such judgements. Worksheets MC2 and 3
indicate suitable approaches to testing line and cover materials, which might be
appropriate extension activities at this stage.
DMA10 Kite decoration
One of the reasons for undertaking a kites project in schools is to give pupils the chance
to decorate them. This is a clear opportunity to link to work they may have done in art
and design and, perhaps, to set up a joint project. This worksheet sets out the issues and
aims to encourage the pupils to experiment.
There is also a potential opportunity to exploit any graphics packages that may be on
the school’s computers. Again, it is possible that a joint project could be established
with ICT in order to draw the shapes and investigate different patterns, lettering and
colours. Worksheet ICT2 might be useful in indicating some of the possibilities.
DMA11 Methods of joining
The wind produces very strong forces and, if the pupils have done the FPT first, they
may well already have discovered that the joints can break under the load. This is
one of the virtues of kite projects: they provide ample opportunities for pupils to
devise ways of reinforcing joints!
The students might do some of the experimenting beforehand (for example,
ensuring that the jointed member is at least as strong as an equivalent member
without a joint), but they could equally well find ways of improving joints that fail
in flight tests. It might be necessary, for instance, either to add extra stiffeners or to
make hollow members solid. Worksheet MC4 provides some additional tasks and
advice that might be appropriate at this stage.
DMA12 3-D modelling
There are a lot of things that have to be got right in a kite design, so testing out ideas early
on is important. This worksheet is intended to encourage pupils to try out their ideas, and
shows a range of kite designs made from reclaimed materials. The pupils may need to be
referred to worksheets FPT7–10 in order to cover some of the basic matters relating to kite
flying.
DMA13–15 Preparations for making the kite
Evaluating the design, detailing the dimensions and planning for manufacture are all key
aspects of preparing to make the kite. It is good modern design practice to get as much as
possible right first time. The pupils are, of course, on a learning curve and they probably
will not get everything right immediately. They might perhaps be encouraged if they are
told to imagine being a test pilot for a new aeroplane design. In that position they would
hope that the designer had tried to think of everything they possibly could, conducted
every useful test they could imagine and double-checked everything before they were
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asked to test the first real prototype. Design modelling is all about this process
of thoroughly exploring all aspects of a design, although this might be a hard
concept for pupils to grasp. Their specification, drawings, ‘lash-ups’, tests, etc.
are all aspects of design modelling, which should lead to a successful flight test
of the first prototype – although most people are likely to overlook something!
2
tn
The questions on DMA13 are intended to get students to start evaluating their
design. The diagrams of alternative line-winding mechanisms are part of a
reminder to them to review all aspects of their design. Worksheet MC5 provides
further guidance and tasks concerning the design of line-winding mechanisms,
which might be appropriate as an extension task for more able pupils.
DMA16 Group manufacturing
Some design briefs for kites might well provide the opportunity for team rather than
individual manufacturing. There are a variety of reasons why teachers might want to opt
for this strategy. For example:
◆ Some of the experimental designs might not have performed well in flight trials. The
pupils will have learnt a great deal from the activity, although their kite does not fly
as well as others.
◆ The National Curriculum requires pupils to work in teams as well as individually,
and this might be the best available opportunity.
◆ There might be a requirement for a small batch to be made up as gifts for school
visitors or to sell as part of a business studies project.
Whatever the reason, the opportunity for the pupils to select a design(s) to develop,
to work on it as a team and to take part in a group manufacturing experience would
be invaluable. Perhaps local engineers or industrialists could help at this point.
The method and prompts in DMA16 should set the pupils off on such a task
constructively and get them into an appropriate frame of mind.
Teachers might choose to tell them at the beginning of the project that after a set
number of weeks, the most promising design(s) will be chosen for development,
and that they will then collaborate on making a batch of the developed design.
There are considerable potential advantages of this strategy from a classroom
management point of view. The FPT is easily managed, but divergent design activity
can be more challenging. A cut-off point for the individual design activities sets up a
situation in which the pupils can engage in open-ended design activity at low risk. If
it all goes wrong, they can enjoy joining in the development of someone else’s design.
It also gives the teacher clear control of the final manufacturing stages and hence the
opportunity to ensure high standards. It is a strategy well worth considering.
DMA17 Evaluating the design and manufacture
This worksheet gives the opportunity for a final check on the design before the manufacturing starts. Most importantly the quality checklist should help the pupils to establish
targets so that they achieve the highest standard of which they are capable in the making
stage. It also sets up the final evaluation of the work once the manufacturing is over.
Of course, from the point of view of the kite project it is too late at that stage, which is
why the emphasis in these worksheets is on reviewing the design and manufacture while
you still have time to do something about it.
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Name
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Key Stage 3 Design and Technology Resource Pack
ICT1–2
M1–2
Sc1–4
S1–3
MC1–5
DMA17
DMA16
DMA13 –15
DMA12
DMA11
DMA10
DMA 9
DMA 7– 8
DMA 6
DMA 4 – 5
DMA1– 3
flexi ble
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SECTION 2
Design and make
progress chart
33
DMA
1
design and make assignment
Kites from different
places and different
times
Kites have been made for thousands
of years all over the world. They have
been used as part of religious festivals,
for scientific investigation, for military
operations, for helping find and rescue
people and for leisure. Worksheets DMA2
and 3 show how the design of kites has
developed through the ages.
flexi ble
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SECTION 2
TA S K 1 a
Find out about another
unusual way in which
kites have been used in
different cultures. Be
prepared to explain to the
group how it would work.
Bamboo
First kites – 400 bc
Banana
leaves
Bird kite
Flat kite
TA S K 1 b
Early kites used materials such as
bamboo, banana leaves, silk and
paper.
(a) Explain why these materials
were used.
(b) Suggest modern equivalents
to these materials.
©
Silk
Paper
Key Stage 3 Design and Technology Resource Pack
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DMA
2
design and make assignment
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SECTION 2
Developments
in kite design
Hardwood
Cotton cambric
Bowed Eddy
– 1891
Box kite – 1893
Alexander Graham Bell developed the box kite further when he was trying to
create a flying machine. (He was also the inventor of the telephone and
president of the National Geographic Society.) In about 1900 Bell worked out
that a triangular box kite would be lighter and stronger and found out that they
fly just as well. He continued to develop
this idea and made compound versions
Alexander Bell
triangular
with more cells.
cell kite
Alexander Bell
compound triangular kite
This was further developed by Louis
Blériot, who added wings to the main
body of the triangular section. (Louis
Blériot was later to become the first
person to fly across the English
Channel.) This shape has been found to
be extremely stable over a wide range of
wind speeds and it was also adopted in
the US, where it became known as the
Conyne kite.
TA S K 2
Blériot or
Conyne kite
©
These kites used cotton for the
cover material.
(a) Explain why cotton was used.
(b) Where else would this kind of
technology have been used?
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DMA
3
Later kites
Parafoil – 1964
Heavy
gauge
mylar
Sled kite
– 1950
Ripstop
nylon
Circoflex – 1996
Deltawing – 1950s
Aluminium
tubing
Fibreglass (or GRP)
TA S K 3
These modern kite designs use
polymers. Look at them carefully
and discuss whether they could
have been made with the sorts
of materials that were used for
earlier kites, like banana leaves
and cotton.
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design and make assignment
DMA
4
Design briefs
flexi ble
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SECTION 2
Now you need to decide exactly what you want your kite to do. Is it to be
decorative or do you want it to perform a particular function? Is it for you or
someone else? The answers to these questions will form the design brief.
The design brief might be set by:
◆ your teacher;
◆ your friends or family;
◆ yourself, because you have a clear idea of exactly what you want to do.
Here are some other ideas for situations where kites may be useful.
As a bird scarer
Farmers need to keep birds away from their crops and newly planted seeds.
Fish farmers also need to deter herons from eating all of their stock. Houses
frequently have a large plate-glass window; birds often do not see these and fly
into them, injuring themselves, sometimes severely. Could a kite be used
effectively to scare the birds away in such situations?
As a display for an event
It is possible to make kites so small and light that they can be flown
by walking indoors. In Japan, mini kites of 10 cm by 5 cm are manufactured,
and in the USA they have been made from microfilm and balsa wood. Small
kites could be designed to provide an exciting flying display at an indoor event.
As a search and rescue beacon
Hill walkers and people sailing in small boats need to attract the attention of
rescue teams if they are in distress. Traditionally they have used flares, which can
be bulky and have to be replaced every year or two. A small, bright kite could be
made to fly above the person to attract help.
As a souvenir
If your town has been twinned with one overseas, consider how you could
convey to the visitors from your twin town the essential character and features
of yours. Several kites could be made and flown together to make a vibrant
display. They could then be given to your visitors afterwards as a souvenir.
TA S K 4
Write a design
brief for your kite.
©
Here is another
interesting design,
made from wood
veneer and tissue
paper:
Key Stage 3 Design and Technology Resource Pack
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DMA
5
design and make assignment
Towards a
specification
flexi ble
st ructures
SECTION 2
As you are designing your kite you will need to make all sorts of decisions. It
will help you to make the right decisions if you have developed a specification
for your design. You will need a list of factors that will make your design a good
one. Some examples of points to consider are given below.
Things to do
Possible considerations
A bird scarer
See if you can arrange to visit a farm,
fish farm or a building with a large
plate-glass window. Find out what
would be the most suitable type of
kite to use as a bird scarer: what size
of kite? and what design would scare
birds away?
A display for an event
Can you work out suitable displays
for the event you have in mind?
Can you find very light materials
to use?
A search and rescue beacon
Examine the type of situation where a
kite might be used. Consider the
possible weather conditions and
fitness of the person using it.
A souvenir
Research your town’s coat of arms,
logo, motto, key landmarks and other
distinguishing features so that your
kite can truly be representative of
the town.
If it is to be a good design it must:
◆ be a design that .............................. ;
◆ be strong enough
to withstand ................................... ;
◆ not need hands to
fly it, so that ................................... .
If it is to be a good design it must:
◆ be light enough to .......................... ;
◆ be visible from ................................ ;
◆ have surfaces that ........................... .
If it is to be a good design it must:
◆ be bright enough to ........................ ;
◆ be light and small enough to ........ ;
◆ be easy to fly because .................... .
If it is to be a good design it must:
◆ show the character of ..................... ;
◆ be symbolic of ................................ ;
◆ be easy to make because ................ .
TA S K 5
(a) For your chosen design brief, list everything you can think of that
should be part of the specification and that will make your design a
good one.
(b) Create the design specification for your kite.
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design and make assignment
DMA
6
Designing a shape
Teddy bear
flexi ble
st ructures
SECTION 2
Kites come in many different
shapes and sizes. Some shapes are
based on insects, birds and other
creatures (whether or not they
normally manage to fly!) However,
cartoon characters, rockets, aircraft
and other shapes can be equally
inspiring. Some examples are
shown below. When you choose
your shape, remember that your
kite needs to be symmetrical.
Concorde
Racing car
Ladybird
Fish
TA S K 6
Sketch shapes that seem
suitable for your design brief.
Then consider each of them
carefully, until you find a
shape that you think would be
appropriate for you to make.
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design and make assignment
DMA
7
Original kites
flexi ble
st ructures
SECTION 2
Some of the kites that you have looked at already may have given you ideas for
your own design. You may want to base it on a traditional design, on some of
the later developments or on one of the more recent innovations. If you wish to
design an original-shaped kite that is yours alone you will need extra help to
make it stable and strong. The following approach to original kite design was
developed in the USA, and might be useful.
Decide whether your chosen shape is short and wide or long and narrow. The
sketches below then show you how to design your kite.
Stiffening the kite
Your kite will need to be stiffened. The main stiffening will only be added to a
forward, central area of the kite because if it were added to the whole area it
would make it too heavy to fly. This main area of stronger bracing creates the
wind-receiving plane. The basic shape of the stiffening frame is the same
whatever the shape of your kite surface.
A second stiffening structure, to strengthen the edges of the kite, is
made from thinner, less rigid materials such as artstraws. This
area of small ribs should overlap the main stiffened area a
little, and has two functions:
◆ to stiffen the leading edge;
◆ to prevent excessive flapping of
the trailing edge.
Areas stiffened by
the thicker ribs
Butterfly –
short and wide
Dotted lines show
lighter ribs
TA S K 7
Sketch your kite
design and show the
pattern of the main
stiffening frame and
the position of the
thin stiffening ribs.
©
Penguin –
long and
narrow
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DMA
8
design and make assignment
flexi ble
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SECTION 2
Stabilising
original kites
If we tried to fly a kite with a flat stiffened surface but without any extra parts it
would twist and slide in the air and be unstable in flight.
Short and wide kites
Short and wide kites require an
extra tail fin. This can be made by
cutting a suitable length of thin
wire, plastic tubing or wood
and sticking it between two discs
(or other shape of your choice) of
fabric or paper (see photograph
opposite). This makes a flat
surface at right angles to the main
area of the kite and so stabilises it
in the other direction.
TA S K 8 a
If your kite is short and wide, design and make a stabiliser to attach to it. A typical area
of a stabiliser for a small kite would be 20–30 cm2.
Long and narrow kites
Long and narrow kites can be stabilised by
making a vertical area from the fabric of the
kite. This can be done by allowing extra
material on the centre line and then folding
it to make a pleat. This is called a vertical fin
(see photograph opposite).
Thin frame
c .1 cm
Fold in and seal
TA S K 8 b
Vertical
tail fin
Original
outline
©
If your kite is long and narrow, a vertical fin
should give sufficient stability. Practise with
scrap paper to see if it will work and to
determine what shape of material you will
need to cut out so that the finished design
looks right after you have made the fold.
Key Stage 3 Design and Technology Resource Pack
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DMA
9
design and make assignment
flexi ble
st ructures
SECTION 2
Investigating kite
materials
Kites from Asian countries have been made traditionally from paper and
bamboo. In the UK, commercial kites nowadays are likely to be made from
polymers, metals and composites. Of course kites are made of the best materials
available at the time. What you can find out about these materials depends on
the resources you have available, but books in your library and the World Wide
Web (WWW) are obvious possibilities.
TA S K 9
(a) Carry out research to answer as many of the following questions as you can.
◆ How is paper made?
◆ Why is handmade Japanese paper the most suitable paper for kites?
◆ What is bamboo and where does it come from?
◆ What are polymers?
◆ What makes polymer sheets particularly suitable for kites?
◆ What are metals?
◆ Where might you use metal on a kite?
◆ Which properties make metal particularly useful for this purpose?
◆ What are composites?
◆ Why might composite tubes be better for kites than bamboo or metal tubes?
(b) Decide on the main components that you will need for your kite. Choose a
suitable material for each one and complete the table below. (Some suggestions
have already been
provided.)
Kite part
Type of material
Wind-receiving plane
Plastic sheet
Stiff bracing
Structa sticks
Thin ribs
Artstraws
Structa
sticks
Wrapped
‘solid’ paper
Hollow
paper tube
Artstraws
©
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design and make assignment
DMA
10
Kite decoration
flexi ble
st ructures
SECTION 2
Many kites are
decorated with fabulous
colours and patterns.
They can be interesting
to look at and exciting,
but sometimes they can
convey a particular
meaning. Some of the
materials that you have
chosen for your kite,
for instance paper, will
be easy to decorate.
Others, like polythene, will present more of a challenge.
You could try watercolours, felt-tip pens and other kinds
of paint. Oil-based paints will work well on some polymer
materials, although watercolours will not. You will need
to explore different ways of decorating polymers until
you find something that works the way you want it to.
Explore patterns and colours to give a
different feel to your design and to
convey a special meaning. For instance,
tartan could represent Scotland; yellow,
Norwich Football Club. Nature has many
wonderful patterns and forms – take the
bee and the hive, for example. Animals
and nature may provide you with some
inspiration.
Painting paper often means getting it wet.
You may already have learnt how to keep
the paper flat when it dries. Some types
of paper may wrinkle when they dry.
You may find that wetting the paper
completely first and then stretching it can
stop the wrinkles. When watercolours dry
they often cause the
paper to curl towards
TA S K 1 0
the coloured side. This not only spoils the
Investigate ways of
look of the kite, but if the leading edge is
decorating the kite
not flat it can cause problems in flight.
material you have
The photographs show a commercially
chosen until you
made paper Chinese butterfly kite and a
have found a way
plastic snake kite. The butterfly kite is beautifully decorated
with which you are
and also shows the principle of the stiff leading edge. The
satisfied.
snake kite also has a stiff leading edge as well as a very long
tail, which is an extension of the main body of the kite.
©
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DMA
11
design and make assignment
flexi ble
st ructures
SECTION 2
Methods of joining
When acting on kites, the wind produces very strong forces. The kite may fail
either under the normal wind load or when it lands. It can fail in one of two
ways: either the wing may pull away from the framework or the framework itself
may break. There are clearly very large ‘dynamic’ (or ‘impact’) loads when the
kite crash-lands. If you have time, investigate the strength of the joints before
you try to fly your first model. The diagrams below show some typical joints and
some simple tests to ensure that they are strong enough.
You might need this kind of joint to stiffen the wing. You could practise making
it and try adapting it to make it stronger.
Does the shape
here matter?
Does creating a
flat surface help?
Weights can
test the strength
of the joint
What if you bind the
stiffeners together?
Does the length
of the overlap matter?
Does the
glue you
use matter?
TA S K 11
(a) Identify all the joints you need to make.
(b) Decide whether you need to do any
testing or redesigning to improve them.
(c) Identify which type of glue will work
best.
(d) Decide whether you wish to design a
kite that folds to make it easier to carry.
These photographs show the
assembly of a
commercially
made paper kite.
It folds in a very
ingenious way
to fit in its box.
©
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design and make assignment
DMA
12
3-D modelling
flexi ble
st ructures
SECTION 2
At this stage you will:
◆ have a good graphic design for your kite;
◆ have a clear design specification;
◆ know what materials you are going to use for
each part of your design;
◆ know how you are going to join the parts together.
Now you have to check that your kite will fly!
Obviously you don’t want to risk crashing and
wrecking your finished design before you have got
it working properly so you might build a fast,
cheap model from scrap materials that will help
to get the details right for the final kite design.
The photo
graphs show
sketch models
of kites made
up from
reclaimed
materials such
as plastic, paper
and fabric.
TA S K 1 2
(a) Build a 3-D model of your kite
and test it to find out more about
how the real design will perform.
(b) Move the towing line until you are
happy with its position.
(c) Decide whether the kite will be
strong enough and make suitable
adjustments. If you need to
strengthen the fabric or spars,
your teacher has extra worksheets
that will help you.
©
Testing a model of your design
in this way gives you the chance
to adjust its performance before
you build a prototype. This is the
time to investigate the effect of:
◆ moving the point at which
the towing line is attached.
This will change the angle at
which the kite flies and
therefore its height;
◆ different patterns of the
stiffening ribs, which may
alter the way the kite flies.
Key Stage 3 Design and Technology Resource Pack
45
DMA
design and make assignment
13
Evaluating the
quality of the design
flexi ble
st ructures
SECTION 2
Before detailing your design and
planning the manufacture you
should check whether the model
meets the requirements. This means
comparing it with your specification.
Card and bamboo – too heavy,
and only flies well in a high wind
Paper
and artstraws –
the way
forward?
Plastic
from carrier
bags and
artstraws –
not stiff
enough
TA S K 13
Evaluate the performance of
your kite model against the
specification by asking yourself
the following questions and
making any changes you
consider necessary.
If everything is all right
you might like to
investigate replacing the
soft drinks can as the
winding mechanism.
Here are some
suggestions:
(a) Which aspects of your
design work well?
(b) Which aspects of your
design need improvement?
(c) Have you considered the
views of all the expected
users?
(d) Have you checked that the
kite flies properly?
(e) Does the kite do all that was
expected?
(f) Does the kite look as
attractive as you had hoped?
©
Key Stage 3 Design and Technology Resource Pack
46
design and make assignment
DMA
14
Detailing the design
flexi ble
st ructures
SECTION 2
It is very important to have a clear idea of exactly what you want to do before
you start to make the actual kite. So far you will have used various kinds of
modelling to help you develop your design. These will have included both
3-D and 2-D models. The 2-D models are most likely to have been sketches
rather than exact drawings.
One of the best ways to examine the detail of a design is to produce a more
accurate drawing. These are generally known as engineering or working drawings. If
it is possible, this kind of drawing is best produced full-size (scale 1:1). This
means there is less chance of your eye being deceived. Obviously if things are
very big – like the buildings designed by architects – then the drawings and
models must be drawn to scale, but the architect must take great care in working
out what a person’s-eye view would be like.
Planning the position of the
art straw stiffeners for the
‘Butterfly original kite’
TA S K 14
(a) Produce a working drawing, like the one shown, which helps with your kite
design.
(b) Sketch the main joints to make sure you know exactly how you are going
to join the different parts (components) of your kite.
©
Key Stage 3 Design and Technology Resource Pack
47
DMA
design and make assignment
15
flexi ble
st ructures
SECTION 2
Planning for
manufacture
It is nearly time to make your kite. A little bit of extra planning, however,
will help you to make it more quickly and effectively. You may not want to
spend any more time planning your design, but it could save you making
time-consuming and expensive mistakes. This means it will speed things up –
not slow them down!
You need to think about all the things you have to do and the best order in
which to do them. For example:
◆ How many parts are there to make?
◆ What materials are you going to use?
◆ How are you going to make each
part?
◆ How are you going to join each part
together?
◆ What is the best order in which to
join the parts?
◆ Should you paint or decorate any of
the parts before they are assembled?
◆ Do you need to test any of the parts
before they are assembled?
Answering such questions should help you to make the best use of the
workshop time available.
TA S K 15
(a) Gather together the materials that
you may want to use and
prepare a cutting list (see opposite).
(b) Identify any parts that can be made
together – for example if they were
to be made of wood and all needed
a plane or saw to make them.
(c) Test the joints, before they are
assembled and difficult to replace, to
check that they are strong enough.
(d) Plan a timetable for the construction
of your kite using one of the
methods described on this sheet.
Part
Number
required
Material
Material size (mm)
Length Width Thickness
Ribs
5
Softwood
200
3
3
Joint
overlaps
2
Softwood
40
30
2
Wings
1
Polythene
400
500
—
A cutting list (helps you to organise the manufacture of
the components)
A flow chart (a
well recognised
way of presenting a plan)
Visit library
WEEK 1
WEEK 2
WEEK 3
WEEK 4
WEEK 5
M T W T F M T W T F M T W T F M T W T F M T W T F
Investigate
Terminal
Start
Investigate
WWW
Any stage at which
the project starts
or stops is delayed
or interrupted
Process
Test possible
materials
Anything that
needs to be done
Complete design
Choose and
obtain materials
Make first prototype
A Gantt chart
Test
(overlapping tasks can be
Analyse and
done on the same day/week
improve design
so that you never waste time)
©
Key Stage 3 Design and Technology Resource Pack
Choose
materials
Decision
The stage at which
a decision needs
to be made
48
design and make assignment
DMA
16
Group manufacturing
flexi ble
st ructures
SECTION 2
Your teacher might let you undertake the manufacturing as a team. You could
even form a small company! If you are forming a manufacturing group, then
your first task is to decide which design to pursue. This can be difficult if you
don’t want to upset anyone.
TA S K 16
(a) Mark the outline of a table (see the example provided below) on a large
piece of paper and sketch each team member’s design in the top row.
(b) If you are all working on the same design brief, look at your specifications
and decide which factors are the most important.
(c) Fill in these factors in the left-hand column of the table.
(d) Choose any of your kites to be the one that you compare all the others to.
This is your datum design. (Design number 3 was chosen as our datum and
this is shown in the table below.)
(e) For each factor put a plus sign in the box if the design does better than the
datum or a minus sign if it does worse.
(f) Discuss and try to improve each item marked with a minus sign. This
should help you choose a group design.
(g) If you wish, you can develop this design as a team so that you are all happy
with it.
1
2
3
4
5
Flying
+
—
D
—
—
Making
+
+
A
+
—
Excitement
—
+
T
—
+
Cost
U
M
©
Key Stage 3 Design and Technology Resource Pack
49
DMA
17
design and make assignment
Evaluating the design
and manufacture
flexi ble
st ructures
SECTION 2
Making sure that products are of the highest possible quality is one of the tasks
regularly faced by manufacturers. This means that they have to check both the
quality of the design and the quality of the manufacturing. One way of testing
the quality of the design is by building a prototype to see how well it meets the
design specification. At various stages during the design process you will have
held discussions with your teacher, who will probably have asked you questions
such as:
◆ Are you sure the kite will work?
◆ Are you sure everyone will like this colour?
Quality checklist
These kinds of questions will contribute to the
ongoing evaluation which is an essential part of
designing; you may have been doing this all the
way through the design process anyway. Now it
is time to double-check.
Do you aim for error-free work?
❑ all of the time
❑ most of the time
❑ just some of the time
❑ only when I feel like it
❑ never
TA S K 1 7 a
(a) Swap your design work with that of a friend.
(b) Ask sufficient questions (like those above)
about your friend’s design.
(c) See if you can spot any improvements that
your friend could make to his/her kite.
So now the design is as good as you can get it,
you must build the highest possible quality
into the manufacturing. Quality checklists (see
opposite) are a good way of focusing attention
on areas where you need to improve and to
evaluate how well you did when you have
completed your project.
TA S K 1 7 b
(a) Fill in a quality checklist like the one
opposite.
(b) Discuss your answers with a group of
friends in order to identify one or two goals
that will improve the quality of the
manufacture of your kite.
(c) Record these goals and use them to review
how well you did after you have completed
your project.
©
Do you check the quality of
your work against the
standards expected?
❑ all of the time
❑ most of the time
❑ just some of the time
❑ only when I feel like it
❑ never
Does your work meet the
expected standard of quality?
❑ all of the time
❑ most of the time
❑ just some of the time
❑ only when I feel like it
❑ never
Are you proud of your work?
❑ all of the time
❑ most of the time
❑ just some of the time
❑ only when I feel like it
❑ never
Are you a positive influence
on your friends and others
in your group?
❑ all of the time
❑ most of the time
❑ just some of the time
❑ only when I feel like it
❑ never
Source: Jim Sage, New Designer Vol.2,
No.1, September 1996.
Key Stage 3 Design and Technology Resource Pack
50
flexi ble
st ruc tures
SECTION 3
IDEAs and
extension tasks
3
tn
he investigating, disassembling and evaluating familiar products and applications (IDEAs) and extension tasks are organised into five areas:
(a) Materials and components (worksheets MC1–5 in this pack)
(b) Structures (S1–3)
(c) Science in design and technology (Sc1–4)
(d) Mathematics in design and technology (M1–2)
(e) ICT in design and technology (ICT1–2)
The first two areas are designed to give opportunities to cover aspects of NC design and
technology, which may not be completely covered by other projects that the pupils have
completed at KS3. They also serve as extension tasks at appropriate points in the DMA
(see TN2). The final three areas provide opportunities to develop links with science,
mathematics and ICT. Links to art and design and the humanities are included within
the DMA. It is not that links to science, mathematics and ICT are any less appropriate,
but it was felt in designing this resource pack that these areas should be clearly within
the teacher’s control.
Notes on worksheets
MC1–5 Materials and components extension tasks
Worksheet MC1 gives an opportunity to explore the strengthening techniques used
in the construction of bags and tents. It allows the pupils to examine other
products related to kites and see to what extent the techniques employed can be
transferred to their design activities. Investigating the design and manufacture of
products is a key aspect of NC design and technology, and a range of tents and bags
should be readily available.
Worksheets MC2–3 suggest ways in which the line (MC2) and cover (MC3) materials
can be tested. This is a good opportunity to discuss what is meant by a fair test, which
is what underpins an understanding of the concepts of stress and strain (i.e. force per
unit area and extension per unit length). For a kite line it is really the force for a given
weight of line that is significant and, more exactly, the force for a particular length and
weight. It would be possible either to fix one variable, for example to take a standard
length of each line material (say 1 m) and then look at the force per unit weight, or to
take the approach indicated in the table on MC2. Whichever route is chosen, some pupils
may need considerable help in getting to grips with completing the table. The more able
pupils would, however, benefit from thinking through the issues. There is a safety concern
if strong line materials are being tested. The floor should be padded to protect against the
fall of large masses, and eye protection should be worn. Testing lower-strength materials
like cotton is obviously safer.
Testing cover materials presents similar difficulties, but more so. There is no standard way
of testing cover materials, so the pupils will have to invent one. In essence, because the
materials will fail as a result of the propagation of cracks, the pupils must find a way of
producing standard cracks. Ito and Komura record their conclusions in their book, but
they do not state the procedure by which they were reached. They provide an interesting
comparison for the results of the pupils’ study. This task should challenge even the
©
Key Stage 3 Design and Technology Resource Pack
52
flexi ble
st ruc tures
SECTION 3
most able students. The context of MC3 might provide a good opportunity for
the examination of a sample of ripstop nylon, as used in modern kites. Torn
sails have little further use and any keen sailors amongst the parents might be
able to reclaim enough for test samples, if not for making whole kites. (The
ripstop nylon used for sails may well be a heavier gauge than that normally
used for kite making.)
3
tn
MC4 provides an opportunity for pupils to explore the kind of joints needed
when fabrics and textiles are attached to a framework. Many kite designs require
such joints (e.g. delta kites), although the FPT included in this pack deals with
construction methods using paper and artstraws. This approach was chosen because
it provides significant teaching and learning opportunities, not because it necessarily
results in the best flying kites. It is quite likely that the pupils’ designs will require more
effort to make, for example the manufacture of a suitable framework from wood and
finding ways of joining it to cover materials. Details of useful knots are also provided on
this worksheet, because they may well be less familiar to pupils than they once were.
The line-winding mechanism is not the most important part of the design, and the
empty drinks cans used in the FPT will be found to work perfectly adequately. Worksheet
MC5 does, however, provide a couple of suggestions for pupils who have completed
other aspects of their designs. Designing a line-winding mechanism would be a useful
extension task for the more able pupils. Both the designs shown in worksheet MC5
could be constructed using dowelling.
S1–3 Structures extension tasks
Kites are structures, and the key NC requirements should be covered through the
designing and making of a kite. These three worksheets introduce some more
difficult areas, but areas that it is necessary for some pupils to cover.
Many kite designs (e.g the parafoil and the flexifoil wing) require fabrics to make
them into 3-D forms. In this case a pattern needs to be made, which can then be
used to cut out the repeating shapes. This is a difficult task and pupils pursuing this
route should be aware that it will require persistence and experimentation. There
are, however, numerous successful kite designs of this kind. The reference to the
work of Ray Merry and Andrew Wilf Jones when they were students is intended to
inspire the pupils into action!
Classifying structural members is a useful exercise in developing analytical skills, just
as it is in other areas like biology and chemistry. If you only have three types of
structural member to think about you can organise your thoughts into these groupings.
There are two other types of structural member that are not mentioned here – torsion
and shear members – but it is a good beginning if the pupils can get the three indicated
on S2 clear in their minds. Structural analysis tends to be done by identifying the type of
structural member (is this a tie? strut? beam? etc.), and then applying the accumulated
expertise in relation to the type identified. Clearly, KS3 pupils’ expertise will be just
beginning to form, but learning to classify structural members correctly will provide a
secure basis for further learning.
For many designs the kite framework is crucial to its success, and the stiffness of the
individual members is the key issue. Artstraws are stiff because they have a comparatively
large hollow section. In considering alternative materials, pupils need to look at the
stiffness-to-weight ratio of the frame materials; worksheet S3 shows how this can be done.
Measuring the gradient is the most elegant way of analysing the results, but if the concept
of a gradient is too advanced then it may be easier to fix the length of the cantilever and
compare the deflection to the weight of the section.
©
Key Stage 3 Design and Technology Resource Pack
53
flexi ble
st ruc tures
SECTION 3
Sc1–4 Science extension tasks
There is an element of mystery surrounding kite flying and, whilst some of it
might be appropriate, kite flying is certainly not completely beyond explanation. Understanding is one of the things that lies behind innovation, because
it leads to a sense of purpose and direction. Without understanding pupils are
often afraid to change anything in case it leads to insurmountable problems.
Whilst by no means providing a full explanation, these four worksheets are
intended to encourage the more technologically imaginative pupils to innovate.
3
tn
Sc1 discusses the atmosphere. It is air movements that generate the lift on the kite,
which enables it to fly. Innovative designs are less likely to perform well first time, in
which case it will be vital to undertake careful tests to distinguish between instability
problems resulting from air movement and instabilities that are inherent in the kite
design. These investigations could take the form of some interesting homework
exercises based on microkites. Very light kites can be flown indoors by simply pulling on
a short line, and would respond to thermal currents.
Worksheets Sc2–4 cover different aspects of the reasons why kites fly. Sc2 enables pupils
to demonstrate lift and drag forces for themselves. This is a valuable exercise by itself,
but if they can go one stage further and learn to add these forces together, it will provide
the basis for the fuller explanation of kite flying provided on Sc4. The addition of
vectors using the triangle or parallelogram forces is now missed out of many
mathematics and science courses, but it is worth the trouble of teaching it here. Elastic
bands are a classic teaching aid for the purpose.
Sc3 is most obviously concerned with measuring the force acting on the kite line,
but it has the hidden agenda of introducing the concept of equilibrium. The force
on the line and the pressure drag (the resultant of the addition of the lift and drag
forces) are equal and opposite. This model of why a kite flies is appropriate in
strong winds, where the pressure drag is very much greater than the weight of the
kite.
Worksheet Sc4 provides an explanation more appropriate to normal flying. The
force from the line and the pressure drag do not act at the same point, and the
consequential rotating ‘couple’ is opposed by the weight of the kite. The visual
explanation provided should be accessible to the more able pupils. In reality, the
point at which the pressure drag acts (the centre of pressure) moves in different wind
conditions; this is one of the key reasons why some designs are more appropriate than
others for particular wind conditions. The structural strength of the kite is, of course,
another key issue.
M1–2 Mathematics extension tasks
One of the major contributions that design and technology can make to the whole
school curriculum is the way in which it can make some subjects come to life. These two
worksheets take two areas of mathematics and show how the skills acquired can be
applied. It is important to check with the mathematics department to find out exactly
when these areas are taught within KS3.
M1 concerns enlargements. Pupils may find a drawing or photograph of a shape that they
would like for their kite, but which is too small. Enlarging the shape by drawing lines
through key points from a central pole is a skill that the pupils have probably mastered,
and this is a chance to use it. The very able pupils may know how to calculate the
necessary ratio from the given kite area; however, making the shape fit onto a large
Sunday supplement magazine should be within the scope of them all.
©
Key Stage 3 Design and Technology Resource Pack
54
flexi ble
st ruc tures
SECTION 3
M2 concerns trigonometry. Pupils may already have learnt to measure the
height of trees in science or mathematics classes, and it is a natural extension
to measure the height at which their kite is flying. Making a simple clinometer
and undertaking such a measurement is a useful extension task for pupils
whose kites fly easily, while other pupils finish their test flights.
3
ICT1–2 ICT extension tasks
Making use of ICT obviously depends on having access to suitable equipment.
These worksheets do little more than note some of the possibilities if they happen
to be available. They are by no means crucial to the success of the project, but can
add further richness to the experience.
tn
ICT1 concerns gathering information. The Internet is an amazing resource and there is
a wealth of information available about kites. As more and more pupils gain access to
the Internet at home or at computer clubs, there is the possibility of setting homework
that can be carried out using this technology. Some design and technology departments
now have access to the WWW, and a class demonstration of the use of the Web as a
design tool may be beneficial. It would be advisable to have found suitable addresses, as
well as trying out search engines, before embarking on the demonstration. A list of
suitable addresses is provided on p. 9 of this pack.
ICT2 concerns computer-aided design and manufacture (CAD and CAM). More and
more schools are getting access to various kinds of CAD/CAM equipment, and most
types can find application in a kite design project. CAD can be used to produce
accurate working drawings. These can be plotted (photocopied and enlarged if
necessary), cut out and used as patterns. It is also possible to get logos or patterns
cut out of sticky-backed plastic, which could be used to decorate the kite. Some
schools now have computer-aided embroidery equipment that could be similarly
used.
The possibility of using a spreadsheet/database to see the effect of changes in the
design on cost should also be noted as a good way of incorporating ICT in design
and technology. This would be particularly appropriate if a group of pupils were
undertaking the manufacture of a small batch, where small changes in the cost of a
single kite can still have a significant impact on the total cost.
©
Key Stage 3 Design and Technology Resource Pack
55
MC
1
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
Bag and tent
construction
Large forces act on sheet materials in a number
of different situations – not just for kites.
Shopping bags carry very great loads when they
are full. Tents
have to withstand
large wind forces
as well as keeping
people dry.
Tents are strengthened
in particular places in
order to ensure that
they do not rip apart
in the wind.
Shopping bags are designed to have a
high strength-to-weight ratio. This means
that they are as light as possible, but are
strong enough to carry a full load of
shopping.
TA S K 1
(a) Examine different types of shopping bag – plastic, paper and fabric – to see how they
are made to be strong and light. Are there any ideas here that you can use in your kite
construction?
(b) Examine a tent that you or a friend own, or look at one in a shop, and see how it has
been made sufficiently strong. Are there any helpful ideas here that you can use?
t
hee
s
n
Tor
rib
nt
e
B
rib
d
e
h
tac
De
(c) The photographs above show some faults that occurred in model kites. Can you
identify similar weaknesses in your kite(s)? Can you think of ways of strengthening
your design to avoid such faults?
©
Key Stage 3 Design and Technology Resource Pack
56
MC
2
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
Testing samples of
materials – lines
Frame materials, and joints in them, have been investigated in DMA11, but we have not yet considered the
material for the body and the line. The line materials
are easy to test, so these will be discussed first. The
force on the line can be measured using a Newton
meter (see Sc3). We need to measure the force that
a line can take before it breaks. The diagram
opposite shows how we can test this.
Long
length
of line
Cotton
Foam pad
The kite must be able to lift its own weight
as well as the weight of the line, so we must
weigh a length of the line. Finding the weight of
a short length of line may be difficult to measure
accurately, so it may be better to weigh a long
length and calculate it (see below).
TA S K 2
(a) Choose three or four possible line materials, including a sample of kite line
if it is available and can be tested safely.
(b) Test the strength of each one and record the force needed to break it in
Newtons (N).
(c) Measure its weight in Newtons and its length in centimetres (cm).
(d) Fill these values in a table like the one shown below.
W
(e) Calculate the weight per unit length and put the answer in the —
L column.
Then calculate the force per weight per unit length and place this in the
final column.
(f) Decide from these last two columns which of the tested materials might be
the best for your line.
Material
©
Force to
break, F (N)
Weight, W
(N)
Length, L
(cm)
Key Stage 3 Design and Technology Resource Pack
W
–
L
W
F / –L
57
MC
3
IDEAs and extension tasks
Testing samples of
sheet materials
flexi ble
st ructures
SECTION 3
Sheet materials will tend to tear when the wind gusts. Also, some materials will
stretch in the wind. A material tears when small ‘nicks’ spread through it when it
is under pressure. You could test samples of
material by making the same size nick in
each one and seeing which will carry the
largest weight before it tears. Be careful to
load it gently!
4 cm
To measure ‘stretchiness’ you need to leave
the weight on for a long time. Perhaps you
can set up your material in one lesson and
see how much it has stretched by the next
lesson. You may need to test each material
in several directions if it is more stretchy in
one direction than another.
Standard
‘nick’
1 cm
Scientists have found sheet materials need certain qualities to make it good for making kites. For a
kite whose area is 0.1 m2 to 0.3 m2:
(a) The mass for every square metre should be less than 100 g.
(b) The material should stretch similar amounts in all the directions that you test it.
(c) If you take a sample of material 1 cm wide and 4 cm long and hang a 1 kg mass carefully on it
as shown, it should return to the same size when the mass is removed. Materials with a low yield
point will stretch permanently under this load.
(d) If you keep loading from the yield point, where it starts stretching permanently, it should stretch
more than 1 cm before it breaks.
Source: Adapted from T. Ito and H. Komura (1983) Kites: the Science and the Wonder, Japan Publications Inc., p. 85.
The scientists found that polyester nonwoven cloth and handmade Japanese
paper, as well as polyethylene film, met
these conditions. There is also a special
material – ripstop nylon – that was
originally developed for sails, but is also a
good kite material. You can probably
guess why it is called ‘ripstop’. It had
threads in a square pattern which stops
any tears propagating.
Another point to consider is how easy it is
to decorate the material used for the kite
body. Test the possible materials with
water colours, marker pens, crayons, paint
or whatever else you would like to
decorate it with, and see if they work.
©
TA S K 3
(a) Test a number of samples
of possible cover materials,
recording:
u the mass at which
stretching starts;
u the amount it stretches
before the material breaks;
u the mass of a square metre,
if possible.
(b) Decide from this data
which might be the best
material to use for the cover
of your kite.
Key Stage 3 Design and Technology Resource Pack
58
MC
IDEAs and extension tasks
Testing different
approaches to joining
4
flexi ble
st ructures
SECTION 3
Having investigated the frame, cover and line materials, all you need to know
now is how best to join them together. Many designs require the cover to be
joined to the frame and you might like to investigate this more carefully.
A hot glue gun is a useful tool for joining plastic material, and your teacher may
suggest that you try other adhesives. If you are stitching your material, what
effect does the spacing and length of the stitches have, the stitch type and the
number of rows?
Your teacher may be able to give you some hints, or else might ask you to devise
suitable tests to find out. (See the task on worksheet MC3.)
TA S K 4
(a)
(ii) Does it matter what
adhesive you use?
(i) Does the width of this
overlap make a difference?
(b) You also need to attach the line.
Which sorts of knot are best?
Again, you might do some
tests, or carry out research into
different kinds of knots and
when and where they have
been used.
(i) Practise tying a reef knot,
a clove hitch and any others
that you can find out about.
(ii) Test the strength and other
important features of each
knot, then try to decide
which type of knot is best
for attaching the line.
©
(iii) Does the stitch
type and spacing
matter?
(iv) Does the number
of rows of stitching
matter?
A
B
Clove hitch – for
joining lines to struts
and attaching the tail
Key Stage 3 Design and Technology Resource Pack
C
Reef knot –
for joining
lines of equal
thickness
59
MC
5
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
Line-winding
mechanisms
So far we have not paid too much attention to the way the line is controlled.
A wide range of line winders is available, however. You will have tried using a
drinks can already and perhaps replaced it with an improved design, as shown
on worksheet DMA13. You might now like to give this component some more
attention and design something special.
One of the tasks that the line winder has to perform is enabling the line to be
wound back neatly, but it is also necessary to allow it to release quickly and
easily. The Korean el-lai reel is hand-held and has rotating spokes. The line can
therefore be fed out carefully, be pulled from the reel or slip off sideways, giving
the kite flyer many options. The Japanese itomaki bobbin-type reel gives similar
options. These two designs are shown in the diagrams below.
TA S K 5
(a) Look carefully at the Korean el-lai reel and the Japanese itomaki bobbin-type reel.
Decide what are the best features of each design.
(b) Design a line-winding mechanism that you feel would be suitable for your kite.
Korean el-lai reel
©
Japanese itomaki bobbin-type reel
– used for kite flying and fishing
Key Stage 3 Design and Technology Resource Pack
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S
1
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
3-D structures
from 2-D pieces
One of the fascinating aspects of working with sheet materials such as textiles,
plastics and paper is the way in which three-dimensional forms can be created
from two-dimensional, flat materials. It depends, of course, on cutting out the
right kind of pattern or template from which the three-dimensional shape can
be created. Most kites can be made from two-dimensional materials. Apart from
remembering to leave on a little extra fabric for the tabs and joins, they are fairly
straightforward to cut out. If you like a challenge, however, you might try doing
some research on Jalbert’s parafoil kite, which is made only of fabric, or a
flexifoil wing kite, which has a stiff spar at
the leading edge.
Jalbert’s
parafoil kite
The flexifoil wing kite was developed in
1971 by two students, Ray Merry and
Andrew Wilf Jones, as part of a class
assignment when they were industrial
design students at Newcastle-uponTyne Polytechnic. Getting it to fly
took a lot of experimenting; this is
reported in Maxwell Eden’s book
Kiteworks:
One day...everything fell into place. After
flipping over on its back, the wing took
off and adopted an improved high angle
of flight. This was a purely accidental
discovery.
Source: M. Eden (1989) Kiteworks:
Explorations in Kite Building and
Flying, Sterling Publishing
Company Inc., p. 79.
Many technological
discoveries are made
by accident, so don’t
be afraid to experiment
with your design. If
you are creative and
persistent, hopefully you
should be just as successful.
Flexifoil
wing kite
The flexifoil wing is
inflated by the wind
Flexible spar at the
leading edge
(bends in flight)
TA S K 1
Can you work out what shape would need to be cut out to make one section
of the parafoil kite or the flexifoil wing?
©
Key Stage 3 Design and Technology Resource Pack
61
S
IDEAs and extension tasks
Identifying
a and comparing
structural members
2
The three main types of
structural member found on
kites are tension members,
compression members and
beams.
flexi ble
st ructures
SECTION 3
E
FAILUR
E
FAILUR
u Tension members have
forces acting on them which
stretch them, and they are
known as ties.
u Compression members have
forces acting on them which
squash them, and they can
be called struts.
Beams
Tension member
(tie)
Compression
member (strut)
u Beams have forces acting
Point load
Distributed load
Cantilever
at right angles to the
member. They can have
point loads (e.g. where
the line is attached to the
kite) and distributed
loads (e.g. the force from
the wind).
These three types of structural
member are shown in the
diagrams opposite.
TA S K 2
E
FAILUR
Tearing from the tension side
©
In the diagrams on
p. 63, draw lines
between the
structural members
on the left-hand
side and the kites on
the right, to show
where each type of
structural member
can be found.
Key Stage 3 Design and Technology Resource Pack
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S
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
Identifying
b and comparing
structural members
2
Box
Delta
Original
Bowed Eddy
©
Key Stage 3 Design and Technology Resource Pack
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S
3
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
Testing
cantilever beams
The lift force on the kite keeps it up in the air and is dependent on the strength
of the wind. With a high wind speed there is a large lift force. If the winds are
light and the kite is heavy it will not fly. The framework is the heaviest part of
the kite, so you will need to find the lightest framework to stiffen the wings.
These stiffeners are known as beams (see worksheet S2) and their resistance to
bending is related to both their shape and the material from which they are
made. Therefore a ‘stiff shape’ and a ‘stiff material’ will need to be found.
TA S K 3
One way to find such a framework is to test the available materials, as shown below.
Deflection
Load (N)
Slope (k) =
Standard length
cantilever beam
15
= 0.75 N/mm
20
15
10
15N
5
20 mm
0
Load
5
10 15 20
Deflection (mm)
(a) Cut different materials and clamp them to form cantilever beams of the same
length. Then do the following:
(i) Place a suitable load on the end of the beam and measure its deflection.
By dividing the value of load in Newtons (N) by the deflection in
millimetres you can find the stiffness of the beam (k) in N/mm. These
values can be placed in column 2 of the table below.
(ii) By repeating step (i) five or six times and drawing a graph for each beam,
as shown in the diagram above, you can find a more accurate value of the
stiffness (k), by
Stiffness, k
k
calculating the
Beam
Weight, W (N)
—
N/mm
W
slope (gradient)
Wooden
of the graph.
dowel
(b) Weigh each beam and
write its weight (w) in
Artstraw
column 3. Then
divide the answer for
Aluminium
k by the weight of the
tube
beam and put the
answer in the last
column. The highest
value of k/w is the
stiffest, lightest beam.
©
Key Stage 3 Design and Technology Resource Pack
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S C
1
IDEAs and extension tasks
The atmosphere
flexi ble
st ructures
SECTION 3
Have you ever stopped to watch birds gliding and soaring, leaves falling in
autumn, felt the breezes near the coast and sheltered from strong winds.
How well kites fly depends entirely on the wind and how it behaves. We can
anticipate some of these effects and we can learn about others by observing
carefully what happens to the kite when we fly it.
Thermal currents will affect the way your kite flies. Some areas of the ground are
heated by the sun more than others, which causes the air to rise, i.e. as a thermal
current. These thermals are used by gliders to gain height. There are other
sources of thermal currents, such as fires and heated buildings. If you made a
microkite (out of balsa wood and plastic film perhaps) you might be able to fly
it on the thermal currents in a room.
TA S K 1 a
If possible, fly your
kite in a flat, open
area and compare
the way it flies
here with how it
flies near to a hill.
Near a hill there
will be an
updraught.
Winds
Trees and buildings
will create turbulent
areas behind them.
TA S K 1 b
Winds
©
If possible, fly your
kite – safely – close
to a building or a
group of trees, and
see if it becomes
unstable.
Key Stage 3 Design and Technology Resource Pack
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IDEAs and extension tasks
S C
Why do kites fly?
2
flexi ble
st ructures
SECTION 3
It is quite difficult to understand why kites fly. It can be made simpler by first
trying to understand the forces at work. The lift force acts perpendicular to the
wind direction and the drag force acts in the wind direction. It is these kinds of
lift forces that keep aircraft, gliders and kites up in the sky. In order to understand these forces better, try out the following experiment.
TA S K 2
(a) Cut a piece of paper 12 cm by 5 cm and bend it round to make a loop
with a curved edge and a flat edge where the sellotape joins it together.
This is an aerofoil shape, which is like the wing of an aeroplane or glider.
(b) Place a pencil in the loop and you will find that the sellotaped edge
drops down.
(c) Now blow over the top of the pencil so that the air that you blow hits the
top of the loop. You should notice that the trailing edge lifts up as you
blow, without anything lifting it up directly. This demonstrates the lift
forces generated by the wind.
(d) You should also have noticed that the loop moves backwards. This
demonstrates the drag force acting on the aerofoil section. This is a kind
of friction force between the air and the surface of the paper.
The paper will move in the
direction indicated by P
Lift force, L
P
Drag
force, D
These diagrams show
the lift and drag forces
that cause such movements. They also show
how the two forces are
Wind
added together using a
‘parallelogram of forces’
to give a single force representing their combined
effect. This is known as
the pressure drag.
Lift force
Drag
force
L
P
D
P is the pressure
drag and the result
of adding L and D.
This will be in the
direction in which the
paper aerofoil moves
©
Combined
force
Which way
does the
pellet go?
Elastic bands can help you to
understand why forces are added
in this way. When the band is
stretched its length represents the
force acting – when it is stretched
further the force gets larger. So if
a band is held between your
thumb and your first finger and
pulled, you can imagine a parallelogram of forces. The combined
force acts along the diagonal of
the parallelogram.
Key Stage 3 Design and Technology Resource Pack
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S C
3
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
Measuring the force
acting on the line
Mass is a measure of the quantity of material in an object. It is measured in
kilograms (kg). When gravity acts on a mass it creates weight. Your mass would
be the same on the earth and the moon, but your weight would be different.
You would actually weigh much less on the moon, because the moon is smaller
and has a much lower gravitational effect. (Have you seen pictures of people in
space suits jumping high on the surface of the moon with apparently little
effort?) Weight is actually a measure of the gravitational force, and is measured
in Newtons (N). On the earth’s surface the effect of gravity (g) causes a force of
9.81 N on a mass of 1 kg, which is why people sometimes say you should
multiply the mass in kilograms by 10 in order to calculate the weight in
Newtons.
Mass × g = weight
Apples give us another way of thinking
about Newtons and kilograms. An apple
weighs about 1 N and has a mass of 0.1
kg. Ten apples have a mass of 1 kg. It is
easy to remember that an apple weighs
1 Newton because of the story of Isaac
Newton: an apple is said to have fallen on
his head when he first discovered gravity.
T
Newton
meter
Mass 0.1 kg
Weight ≈ 1 N
It is gravity that pulls your kite
downwards, and you can measure
the ‘lift force’ that is keeping it
flying with a Newton meter.
Knowing this force would help
you to choose an appropriate
material for the line, but
measuring it can also help you
gain a further understanding
of the forces acting.
Drag force
Weight of
the line
TA S K 3
Try flying your kite (either the one
you have made or a commercial
design) with a Newton meter or
spring balance attached to the line.
The Newton meter will show the
force acting on the line.
©
1 kg of
apples weighs
approximately
10 N
Key Stage 3 Design and Technology Resource Pack
The line will be curved
in reality because of
the combined effect of
its weight and the drag
force
67
S C
4
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
The forces acting
on a kite
The model shown below will describe adequately the forces acting on a kite in
a strong wind, i.e. where they are very large. The pressure drag, P, which acts
perpendicular to the surface, is equal and opposite to the force in the line, T.
P
T=P
P
L
L
P
or
Triangle
of forces
T
Measure T with
a Newton meter
D
You might think that the value of the lift
force would be quite near to the weight
of the kite, but you have to remember
that it has to lift the line as well. Even
if you take this into account, you
might still find that there is an
error. This is because the forces
acting on a kite are a little more
complicated than the simple
‘strong winds’ model.
D
Wind
P
F
T
Mg
P = the pressure drag
F = the friction drag
T = the tension or pull in the line
Mg = the weight of the line
It is hard to calculate the values, but the
cause of the error is the friction drag, F,
which acts along the surface of the kite. You
should, however, be able to see why one of
the golden rules of kite flying is to attach the line so that when pulled it acts
above the kite’s centre of gravity. The combined action of T and P tends to turn
the kite anticlockwise, and it is the effect of the weight that stops this happening.
TA S K 4
Measure the force on the line (T) with a Newton meter. This value can now be
used for the pressure drag (P), as they are equal.
Calculate or estimate the angle at which your kite was flying (see worksheet M2,
or you can assume 15°) and now, on graph paper, draw to scale a line representing P at this angle (75° to the horizontal). By either drawing the rectangle
or triangle of forces as shown, you can now find the lift and drag forces acting
on the kite. The vertical measurement represents L (the lift) and the horizontal
represents D (the drag).
©
Key Stage 3 Design and Technology Resource Pack
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M
1
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
Enlargements
Ladybird
Car
Concorde
You need to make kites with different areas in order to get them to fly well
when they are made from different materials. Very small kites would need to be
made from light materials such as balsa wood and clingfilm. Large kites could
be made from cotton and bamboo. You should find that paper and artstraws
work well for kites with an area about the same as a weekend magazine.
The kind of original kites described in this pack have a typical area of
1,000–2,000 cm2. This is about the same size as a double sheet from a large
Sunday supplement magazine. However, you might find either a photograph or
a drawing of a shape that you would like to use for your kite, but which is the
wrong size. It might be a shape from nature – a bird, perhaps, or an animal –
or a cartoon character. The shape can be enlarged as shown below.
Pole in the
centre of
enlargement
for the
butterfly
Lines through
the pole and
key points
e
1 Measure line, e, from the
centre of the enlargement.
2 Multiply this length by the
scale factor (shown here
as 2).
3 Mark out this length, E, from
the centre of the enlargement to the new point.
4 Repeat for all the key points
of your chosen shape.
5 If the scale factor is 2, the
area is 2 2, or 4 times the
original area. Calculate how
much bigger in area your
new kite is.
E
TA S K 1
Find a small picture
of a shape you would
like for your kite and
enlarge it as shown in
the diagram.
©
Key Stage 3 Design and Technology Resource Pack
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M
2
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
Measurement
of height
When you have got your kite to fly in the way that you want it to, you can try to
measure the height at which it flies. It is easier to measure the height of your kite
when it is flying steadily, so you must hope that the day you pick has calm
winds. You will need the help of at least one of your friends in order to carry out
all the measurements.
TA S K 2
(a) First you must find a protractor in
order to measure angles, and a small
tube of about 20 mm diameter.
They will not be damaged, but if
you cannot find them easily, roll
up some thin card to make the tube
and mark a few angles on a piece
of card. Join them together with
tape and then attach a plumb line,
as shown in the diagram on the
right.
Narrow tube –
approximately
20 mm in
diameter
Clinometer
Protractor or
marked card
Plumb line
(b) The device you have made is called a clinometer, and is used to measure
angles. Make sure your friend is standing directly under the kite and then
look at your kite through the tube. Mark the angle that the plumb line
makes with vertical. (This is where you might need the help of another
friend, but you can probably hold the plumb line in position!) The
person standing under the kite must walk back to where you are
standing and count the number of paces they take. If you measure
the length of one pace, then you will be able to calculate the
distance they walked. Once you know this distance and the angle,
you can calculate the height of the kite. There is a reminder
below if you have forgotten your trigonometry.
tan
y (opposite)
=
x (adjacent)
C
y = x.tan
Altitude
y (altitude)
A
B
x
(Horizontal distance from you to the kite)
©
Remember to add
your height!
Key Stage 3 Design and Technology Resource Pack
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1
IDEAs and extension tasks
flexi ble
st ructures
SECTION 3
Gathering information
and the Internet
You might already know what the
Internet is and you may have already
used it, but have you thought of using it
to help with your projects in design and
technology? If you don’t already know
what the Internet is, then try to imagine
hundreds of thousands of computers all
around the globe, all connected together.
People use the Internet to send electronic
mail (e-mail) messages to one another,
and this is becoming quite a popular way
of communicating. It is, however, the
growth of the World Wide Web (WWW)
that really captures people’s imaginations. The WWW is like a gigantic encyclopaedia or CD-ROM with information
on every conceivable topic.
You can use a computer that
is connected to the Internet
to browse, or ‘surf ’, around
thousands of sites. You might
be able to find useful information for your kite design from
all over the world – looking at,
and sometimes downloading,
pictures and text.
The Internet and the WWW
do not have to be just oneway traffic. User groups, with
members in different
countries, form to discuss
topics of interest. You could
ask questions, look at other
people’s designs and even
show other pupils your work.
You could be comparing
notes on kite designs with
pupils not only in this
country, but anywhere – the
United States, Japan, etc.
©
TA S K 1
If you have access to the WWW, see if you can
find useful information concerning kite design.
Can you use the Internet to make contact
with other pupils interested in kite design?
Try visiting http://www.designit.org /
Key Stage 3 Design and Technology Resource Pack
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2
IDEAs and extension tasks
Computer-aided design
and manufacture
(CAD and CAM)
flexi ble
st ructures
SECTION 3
Computer software and equipment is now available which can help you with your
designing and making. This worksheet suggests a few possibilities that you can
try out if you have the opportunity.
Working drawings often need to
be altered when some new information becomes available. There
are a number of computer-aided
design programs available. They
take a little bit of time to learn,
but once you have drawn your kite
using such software it is very easy
to alter. You can also print out the
drawing to give you a pattern if a
suitable plotter is available.
The effects of changing colours and
patterns are sometimes hard to imagine.
If you have drawn your kite with software,
which includes options to colour in
different areas in various colours, then you
can see what happens before you try it out.
It is still a good idea, however, to try it out
with materials you are not too concerned
about before you make the real kite.
A logo can add something special
to your design. If you draw a shape
using computer software and your
school has the right equipment,
then you might be able to get the
logo cut out of sticky-backed
plastic and even embroidered
onto a textile material.
TA S K 2
Find out if your school has any CAD/CAM equipment and try to think of
ways that you can use it in your kite project.
©
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