Presented by:
Monique FUERI
Director Operational Performance
ACN/PCN module in PEP
Content
 ACN/PCN method
 ACN determination
 ACN/PCN PEP module
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
 Conclusion
ACN/PCN module in PEP
April 2007
Page 2
Content
 ACN/PCN method
 ACN determination
 ACN/PCN PEP module
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
 Conclusion
ACN/PCN module in PEP
April 2007
Page 3
ACN/PCN method
• Aim:
Considering
a runway with a given bearing strength, can a
given aircraft with a given load operate on this runway
without damaging the pavement ?
• Numerous methods developed:
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
44
methods in USA in the 80’s
• 1982: ACN/PCN method developed by ICAO
• Former official ICAO method: LCN (Load Classification
Number) still sometimes used.
ACN/PCN module in PEP
April 2007
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ACN/PCN method
Pavement Classification number:
• The PCN expresses the bearing capacity of a pavement
for unlimited operation
• The PCN is provided by airport authorities
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
• The PCN is qualified by:
Pavement
type
Subgrade strength category
Tire pressure category
Pavement calculation method
ACN/PCN module in PEP
April 2007
Page 5
ACN/PCN method
Pavement Classification Number:
• The PCN expresses the bearing capacity of a pavement
for unlimited operation
• The PCN is provided by airport authorities
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
• The PCN is qualified by:
Pavement
type
Subgrade strength category
Tire pressure category
Pavement calculation method
ACN/PCN module in PEP
Pavement type
R : rigid
F : flexible
April 2007
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ACN/PCN method
Pavement Classification Number:
• The PCN expresses the bearing capacity of a pavement
for unlimited operation
• The PCN is provided by airport authorities
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
• The PCN is qualified by:
Pavement
type
Subgrade strength category
Tire pressure category
Pavement calculation method
ACN/PCN module in PEP
Subgrade strength category
A : high
B : medium
C : low
D : ultra low
April 2007
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ACN/PCN method
Pavement Classification Number:
• The PCN expresses the bearing capacity of a pavement
for unlimited operation
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
Tire pressure category
(maximum permissible tire pressure)
• The PCN is provided by airport W
authorities
: no limit
X : to 1.5 MPa
Y : to 1.0 MPa
• The PCN is qualified by:
Z : to 0.5 MPa
Pavement
type
Subgrade strength category
Tire pressure category
Pavement calculation method
ACN/PCN module in PEP
April 2007
Page 8
ACN/PCN method
Pavement Classification Number:
• The PCN expresses the bearing capacity of a pavement
for unlimited operation
• The PCN is provided by airport authorities
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
• The PCN is qualified by:
Pavement
type
Subgrade strength category
Tire pressure category
Pavement calculation method
ACN/PCN module in PEP
Pavement calculation method
T : technical
U : using a/c experience
April 2007
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ACN/PCN method
Example :
PCN 58 R / B / W / T
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
The bearing capacity of a rigid pavement resting
on a foundation of medium strength has given,
by technical assessment, a PCN = 58.
There is no tire pressure restriction.
ACN/PCN module in PEP
April 2007
Page 10
ACN/PCN method
Aircraft Classification number:
• The ACN expresses the relative effect of an aircraft on a
pavement for a specified standard subgrade
• ACN depends on aircraft parameters and runway
parameters:
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
Aircraft
parameters:
weight, C.G. position,landing gear geometry (twin gear or
bogie), tire pressure
Runway
parameters:
pavement type, subgrade category
ACN/PCN module in PEP
April 2007
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ACN/PCN method
• Unrestricted operation if ACN is less or equal to PCN
• Overload operation is possible depending on country and
airport policy.
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
ICAO
rule for overload operations:
– 10% PCN margin for flexible pavements
– 5% PCN margin for rigid pavements
– Annual number of overload movements less than 5% of total
annual movements
ACN/PCN module in PEP
April 2007
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ACN determination
• ACN for Airbus aircraft can be determined using the
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
Airplane Characteristics for Airport Planning Manual
ACN/PCN module in PEP
April 2007
Page 13
Content
 ACN/PCN method
 ACN determination
 ACN/PCN PEP module
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
 Conclusion
ACN/PCN module in PEP
April 2007
Page 14
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
ACN determination
ACN/PCN module in PEP
April 2007
Page 15
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
ACN determination
ACN/PCN module in PEP
April 2007
Page 16
Content
 ACN/PCN method
 ACN determination
 ACN/PCN PEP module
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
 Conclusion
ACN/PCN module in PEP
April 2007
Page 17
ACN/PCN PEP module
• With the increasing number of Airbus aircraft and Airbus
operators, more and more destinations have low strength
runways.
• Runway loading aspects start playing an important role in
landing fee determination.
• ACN determination with the curves presently published
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
may be fastidious and lead to errors.
ACN/PCN module in PEP
April 2007
Page 18
ACN/PCN PEP module
• New PEP module: ACN and LCN calculation
ACN/PCN
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
ACN/PCN method
Runway
Calculation
LCN
method
ACN/PCN module in PEP
April 2007
Page 19
ACN/PCN PEP module
• Compute ACN and LCN for every pavement type for given
aircraft data
• Compute maximum aircraft weight for a given runway
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
• Possibility to introduce the PCN value of each runway in
the airport database managed by the airport manager is
being studied
• Provide a graphical output: ACN function of aircraft C.G.
for a given pavement type
ACN/PCN module in PEP
April 2007
Page 20
ACN/PCN PEP module
• Center of Gravity Position Influence
ACN’s defined
at MRW and
max aft CG
A330-200 ACN's Flex Cat. B
250 15
20
25
30
35
40
ACN 65 F/B
230
MTOW 230 000 kg
ACN 60 F/B
ACN 55 F/B
210
ACN 50 F/B
190
ACN 45 F/B
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
170
150
MLW 182 000 kg
MZFW 170 000 kg
ACN 40 F/B
ACN 35 F/B
<-- Flight
130
ACN 30 F/B
<-- Take-Off & Landing
Landing -->
Flight -->
Take-Off -->
110
10
15
20
25
30
35
40
Tires 1400x530R23 PR36
Tire Pressure (loaded): 14.2bar (206psi)
max
45aft CG Position: 37.5% MAC
Max Taxi Weight: 230.9t
Same ACN but several tons of Payload/Fuel difference
ACN/PCN module in PEP
April 2007
Page 21
Content
 ACN/PCN method
 ACN determination
 ACN/PCN PEP module
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
 Conclusion
ACN/PCN module in PEP
April 2007
Page 22
Conclusion
• New ACN/PCN module will be fully integrated in the PEP
user-friendly interface
• It will allow:
computation of a given aircraft
Maximum aircraft weight for a given runway
LCN computation
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document.
ACN
• Availability: mid-2008
ACN/PCN module in PEP
April 2007
Page 23