1. 14 th Performance & Operations Conference Bangkok, 4-8 April 2005 One/two engine taxi Review of associated recommendations Presented by: Michel DOCUS Group Manager A320 Family Operational Standards

2. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 2 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Contents Introduction Why should I perform an engine out taxi ? Conditions to perform an engine out taxi F.A.Q. : Do I need APU ? Can I perform an engine out taxi in icing conditions ? Can I brake during engine start/shutdown on S.A. ? Can I perform the flight control check ? Conclusion

3. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 3 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Introduction Taxi time increases due to : Airport congestion Increased airport size Airport regulations One Engine Out allowed on Single Aisle and A330 Two Engine Out allowed on A340 Engine out taxi already covered in FCOM 3.04.90 and Getting to grips with fuel economy brochure Increased use of one or two engine out taxi

4. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 4 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Contents Introduction Why should I perform an engine out taxi ? Why should I perform an engine out taxi ? Conditions to perform an engine out taxi F.A.Q. : Do I need APU ? Can I perform an engine out taxi in icing conditions ? Can I brake during engine start/shutdown on S.A. ? Can I perform the flight control check ? Conclusion

5. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 5 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Benefits of engine out taxi Reduce CO2 emission (Kyoto protocol) Save fuel Save brakes Reduce turn around time Airport regulations

6. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 6 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Benefits of engine out taxi Reduce CO2 emission Kyoto protocol valid since 16 feb 2005 –Reduce CO2 emission to 1990 level –1 ton of burnt fuel = 3.15 tons of CO2 Today no specific regulation edicted by ICAO Future tax on airplane fuel ??? –Could be part of the measures taken by ICAO

7. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 7 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Benefits of engine out taxi Fuel economy :

8. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 8 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Benefits of engine out taxi Fuel economy per aircraft : Single Aisle : –average of 4.5 cycles/day 65700 kg / year / aircraft –180kg per day : 65700 kg / year / aircraft Long Range : – average 2.5 cycles/day 91250 kg / year / aircraft –250kg per day : 91250 kg / year / aircraft Results based on 8 minutes with engine out Results based on 8 minutes with engine out Taxi on some airports may reached 45 minutes !!! Taxi on some airports may reached 45 minutes !!!

9. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 9 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Benefits of engine out taxi Brakes saving Lower thrust Lower taxi speed Reduced number of brake application Brake saving

10. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 10 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Benefits of engine out taxi Reduced turn around time Reduced brake temperature Prevent Brakes Hot warning Less takeoff delays

11. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 11 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Benefits of engine out taxi Airport regulations To enhance safety but shutting down the engine near the air bridge To reduce Noise –Getting to Grips with Aircraft Noise brochure

12. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 12 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Contents Introduction Why should I perform an engine out taxi ? Conditions to perform an engine out taxi Conditions to perform an engine out taxi F.A.Q. : Do I need APU ? Can I perform an engine out taxi in icing conditions ? Can I brake during engine start/shutdown on S.A. ? Can I perform the flight control check ? Conclusion

13. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 13 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Airbus recommendations before applying engine out taxi Not recommended at high gross weight or uphill slope High thrust increases Foreign Object ingestion risk –Engine damage Slow or tight taxi turn more difficult at high gross weight Not recommended on slippery taxiways More difficult to steer with asymmetric thrust

14. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 14 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Airbus recommendations before applying engine out taxi Respect of the engine stabilization times Minimum of 2 min engine warm up and 3 min cooldown time To thermally stabilize the engine hot sections In case of mechanical event,return to the gate may be required for maintenance action

15. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 15 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Contents Introduction Why should I perform an engine out taxi ? When should I perform an engine out taxi ? F.A.Q. : F.A.Q. : Do I need APU ? Do I need APU ? Can I perform an engine out taxi in icing conditions ? Can I brake during engine start/shutdown on S.A. ? Can I perform the flight control check ? Conclusion

16. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 16 14th Performance & Operations Conference Bangkok, 4-8 April 2005 F.A.Q. Do i need APU to taxi with engine out ? APU use considered in the engine out taxi : –APU use part of the SOP –Minimize electrical transients –Prevent smells/fumes entering the air conditioning during taxi in Start APU before arriving at the gate and before engine shutdown Minimizing APU use helps save fuel and reduces maintenance –APU max consumption : between 125 (SA) and 290 kg/hr (A3456) But APU is not necessary for engine out taxi

17. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 17 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Contents Introduction Why should I perform an engine out taxi ? When should I perform an engine out taxi ? F.A.Q. : Do I need APU ? Can I perform an engine out taxi in icing conditions ? Can I perform an engine out taxi in icing conditions ? Can I brake during engine start/shutdown on S.A. ? Can I perform the flight control check ? Conclusion

18. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 18 14th Performance & Operations Conference Bangkok, 4-8 April 2005 F.A.Q. Can I perform engine out taxi in icing conditions ? FCOM / AFM : Engine anti ice must be on when icing conditions exist or are anticipated: –To avoid ice accretion on nacelle and fan Engine anti ice operative only on a running engine

19. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 19 14th Performance & Operations Conference Bangkok, 4-8 April 2005 F.A.Q. In icing conditions,non running engine will not necessarily ice : Icing conditions do not mean necessarily ice accretion Non running engine less prone to nacelle and fan icing –Due to absence of fan airflow speed But,difficult to assess conditions under which a non running engine will ice.

20. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 20 14th Performance & Operations Conference Bangkok, 4-8 April 2005 F.A.Q. Consequences if engine out taxi in icing conditions : Possible delayed takeoff : –If engine acceleration requested before takeoff –Due to warm up, up to 5 minutes (depending on engine) before engine acceleration, on the last started engine

21. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 21 14th Performance & Operations Conference Bangkok, 4-8 April 2005 F.A.Q. Degraded control on slippery taxiway due to : Use of assymetric engine anti ice increases ground idle thrust Conclusion : Do not delay engine anti-icing, to avoid possible ice ingestion and engine damage Engine out taxi not recommended if anticipated ice accretion (freezing rain,freezing drizzle,freezing fog or heavy snow…)

22. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 22 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Contents Introduction Why should I perform an engine out taxi ? Conditions to perform an engine out taxi F.A.Q. : Do I need APU ? Can I perform an engine out taxi in icing conditions ? Can I brake during engine start/shutdown on S.A. ? Can I brake during engine start/shutdown on S.A. ? Can I perform the flight control check ? Conclusion

23. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 23 14th Performance & Operations Conference Bangkok, 4-8 April 2005 F.A.Q. On Single Aisle,why does Airbus recommend to not brake during engine start or shutdown, if the aircraft is moving ? On A320 family,electrical transients during engine start/shutdown –Automatic switch of BSCU channel Alternate braking temporarily takes over Greater braking efficiency in ALTN for same pedal deflection Possible jerk if the aircraft is moving

24. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 24 14th Performance & Operations Conference Bangkok, 4-8 April 2005 F.A.Q. On Single Aisle,why does Airbus recommend to not brake during engine start or shutdown, if the aircraft is moving ? (contd) Braking is allowed during engine start/shutdown FCOM wording clarified at next revision (sept 05) : during engine start or shutdown,a slight jerk forward may occur if brakes are applied when the aircraft is moving

25. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 25 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Contents Introduction Why should I perform an engine out taxi ? Conditions to perform an engine out taxi F.A.Q. : Do I need APU ? Can I perform an engine out taxi in icing conditions ? Can I brake during engine start/shutdown on S.A. ? Can I perform the flight control check ? Can I perform the flight control check ? Conclusion

26. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 26 14th Performance & Operations Conference Bangkok, 4-8 April 2005 F.A.Q. Can I perform the flight control check during an engine out taxi ( All FBW) ? On a system point of view,no objection Ground tests found fully acceptable But, recent isolated in-service event led to necessity of flight control check in takeoff configuration, in terms of electrical and hydraulic power. Therefore with all engines started. As all the failures cannot be automatically monitored

27. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 27 14th Performance & Operations Conference Bangkok, 4-8 April 2005 F.A.Q. Can I perform the flight control check during an engine out taxi ( All FBW) (contd) ? New procedure to be incorporated to all FBW for commonality purposes : Can be performed during engine warm up period. The flight control check has to be performed after all engine starts, followed by the autobrake max selection.

28. © AIRBUS 2005 S.A.S. All rights reserved. Confidential and proprietary document. One/two engine taxi 28 14th Performance & Operations Conference Bangkok, 4-8 April 2005 Conclusion Engine out taxi already allowed (FCOM 3.04.90) Helps to reduce : Fuel consumption and CO2 emission Brake wear Turn around times On SA,braking allowed during engine start/shutdown Flight control check to be performed after all engines start