Safety and Airspace Regulation Group
27 July 2016
Policy Statement
Origination and approval of lateral data referenced to the WGS84 ellipsoid, contained
within an Airspace Change and/or ICARD Request.
1. Scope:
1.1 This process is intended to clarify the roles and responsibilities of individuals and organisations
involved in the origination and approval of Latitude, Longitude, tracks and distances referenced to
the WGS84 ellipsoid that are to be published in the UK IAIP.
1.2 The requirement for Lateral Data referenced to the WGS84 ellipsoid arising from either:
a. The Formal Airspace Change Process (see CAP 725), or other Airspace Change that does not
require the formal/full ACP process is progressing towards the later stages and the need for this data
has been identified by the sponsor and approved in principle by the nominated CAA Case officer.
And/or
b. A Significant Point Name Code (5LNC) is required and the proximity check (as detailed in the CAA
Policy Statement) has been carried out using ICARD.
2. Responsibilities
2.1 The Change Sponsor shall identify, originate, collate and supply data, first to the CAA for
approval and subsequently to NATS/AIS for AIP promulgation.
2.2 The Regulator (CAA) shall approve the submission, or feedback areas that require attention.
2.3 NATS AIS shall store the data and publish the data on the agreed AIRAC Cycle to the required
standards.
3. Actions
3.1 Change Sponsor – The origination/collation of new or amended lateral data referenced to the
WGS84 ellipsoid.
The change sponsor shall thoroughly read the Instructions worksheet in the CAA spreadsheet before
submission.
3.1.1 The CAA WGS84 spreadsheet template shall be the vehicle for the submission of new WGS84
Lateral data. Detailed instructions on completion and required accuracy are contained in the
instructions sheet. A file name based on the project title and a version control suffix shall be
incorporated when supplied by the sponsor, starting with v1. The sponsor section of the ‘Details &
Approval’ worksheet shall be completed.
3.1.2 The Change Sponsor shall ensure mathematical calculation and/or collation of the required
new WGS84 lateral data by suitably qualified person or organisation and incorporate it into the
‘Lat_Long_Track_Dist’ worksheet. Of note:
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Accurate descriptions and parameters used in any calculations are required.
The data shall be supplied to the highest level of precision available, without rounding.
No attempt should be made to apply magnetic variation by the change sponsor.
The minimum accuracy and resolution for coordinates, distances and bearings are detailed
within the spreadsheet.
If a new/amended WGS84 Lat/Long is NOT part of a Route or Area, no further info is required, but
where applicable, the subsequent impact of this point on ENR 3.1/3.2/3.3 (routes) and ENR 2.1/ENR
5.1/AD 2.17 (areas) shall be included. There are dedicated worksheets for each of these sections.
3.1.3 The completed spreadsheet along with any other supporting documents should be submitted
to [email protected] where it will be forwarded onto the relevant CAA case officer.
3.2 CAA Regulator - Approval of data referenced to the WGS84 ellipsoid.
3.2.1 ‘Lat_Long_Track_Dist’ worksheet
The CAA case officer will ensure that the content of the ‘Lat_Long_Track_Dist’ worksheet is
scrutinised to an appropriate level by a suitably qualified individual within CAA, who will conclude
via mathematical and/or graphical means that the data entries are either:
Approved– The supplied lateral data is fit for purpose – the adjacent ‘CAA Approval Status’ column
will be marked as ‘Approved’ , or
Not Yet Approved – If any part of the supplied lateral data is not fit for purpose in its current format.
If this is the case, items that require further attention or clarification will be described in the
adjacent ‘CAA Comments’ column and ‘Not Yet Approved’ shall be added to the adjacent ‘CAA
Approval’ Status column. Summary details will link through to the ‘Details & Approval’ worksheet
where the WGS84 Data approval Name/Status/Date details should also be completed. This will be
returned to the CAA Case Officer.
3.2.2 ENR 3.1/3.2/3.3 and ENR 2.1/ENR 5.1/AD 2.17 worksheets
The CAA case officer will ensure the content of the remaining worksheets ENR 3.1/3.2/3.3 (routes)
and ENR 2.1/ENR 5.1/AD 2.17 (areas) are scrutinised to an appropriate level and will conclude that
the entries are either
Approved– The AIP ‘mock up’ data is fit for promulgation - the adjacent ‘CAA Approval Status’
column will be marked as ‘Approved’ , or.
Not Yet Approved – If any part of the worksheets ENR 3.1/3.2/3.3 (routes) and ENR 2.1/ENR 5.1/AD
2.17 (areas) are not fit for promulgation. If this is the case, items that require further attention or
clarification will be described in the adjacent ‘CAA Comments’ column and ‘Not Yet Approved’ shall
be added to the adjacent ‘CAA Approval’ Status column. Summary details will link through to the
‘Details & Approval’ worksheet where the CAA Case Officer should complete the Name/Status/Date
details.
The CAA Case Officer shall return the spreadsheet to the sponsor. If any of the ‘CAA Approval Status’
columns contain ‘Not Yet Approved’ the Sponsor is required to re-supply the spreadsheet including
new or amended data where applicable and adding a new version number to the submission (v2
v3etc). This process to be repeated until the CAA Case Officer Approves all the detail.
3.3 Change Sponsor – Submit AIP Change Request:
3.3.1 The Change sponsor is responsible for submitting the AIP Change Request, including reference
to all affected sections.
3.3.2 Evidence that CAA approval has been attained (the spreadsheet with all entries approved) shall
be provided as an attachment with the AIP change request.
3.4 NATS AIS – Promulgate Information:
3.4.1 Upon receipt of the AIP Change request, the data should have the appropriate magnetic
variation applied and/or be rounded to meet agreed publication standards where applicable. Any
issues with the request should be pushed back to the change sponsor and/or CAA case officer as
applicable.
Any questions regarding the process should be sent to [email protected]