Download presentation
Presentation is loading. Please wait.
Published byFrancine Parrish Modified over 9 years ago
1
Landing in CONF 3 – Use of reversers Hélène REBEL Head of A330/A340 Operational Standard Presented by:
2
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 2 General considerations Airbus Flight Crew Operating Manuals recommendation Maximize safety margins CONF FULL – Maximum Reverse thrust
3
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 3 General considerations Above all, the first considerations must be: The aircraft landing weight The runway length The braking means The runway surface conditions The tailwind Autoland not certified in CONF 3 (CONF 15/20) for A300/A310 aircraft family For economics, airlines could envisage: Approach in CONF 3 Idle or no reverse thrust at landing All operational and economics consequences have to be considered.
4
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 4 Content General considerations Fuel economy estimation Additional considerations: Other operating cost considerations Operational consequences Pro and Cons: Summary Conclusion
5
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 5 Fuel economy estimation Depends on several parameters as: – Aircraft / Engine type – Aircraft weight during the approach – Approach speed – Autobrake selection – Airport elevation – The ISA conditions – … Fuel economy estimation
6
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 6 Fuel economy estimation Simulation hypothesis Airport elevation: Sea Level ISA conditions Approach speed VLS + 5 knots Autobrake LO 2 aircraft weights: light and heavy weights
7
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 7 Fuel economy estimation Simulation hypothesis – Cont’d 1500 ft: S/F configuration for landing: CONF 3 or FULL REV IDLE LANDING AT REV IDLE 0 kt 1500 ft: S/F configuration for landing: CONF 3 or FULL IDLE THRUST LANDING WITH NO REV 0 kt 1500 ft: S/F configuration for landing: CONF 3 or FULL 70 kts * REV IDLE REV MAX LANDING AT REV MAX 0 kt * 85 kts for Wide Body aircraft
8
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 8 Fuel economy estimation RESULTS Average fuel consumption increase in kg between REV MAX and REV IDLE REV IDLE and No REV CONF FULL and CONF 3 CONF FULL / REV MAX and CONF 3 / REV IDLE A320 family 10 to 15 15 to 20 22 10 to 15 5 to 15 15 to 30 20 to 40 A330 family 25 to 45 40 to 60 55 10 to 15 10 to 25 40 to 55 60 to 75 A340- 200/30035405515 15 to 20 5060 A340- 500/60065 85 to 90 10151057595 A300 family 30 to 40 50 to 65 33 15 to 25 15 to 30 5080 Light weight Heavy weight
9
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 9 Content General considerations Fuel economy estimation Additional considerations: Other operating cost considerations Operational consequences Pro and Cons: Summary Conclusion
10
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 10 Other operating cost considerations Direct Maintenance Cost (DMC) is mainly affected by thermal cycling or age of the materials Deployment of reversers has a minor impact in DMC Thrust Reversers Lower reversers thrust Reduction of FOD risk and associated maintenance No advantage to do a landing without reversers
11
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 11 Other operating costs consideration Tire wear is affected by several parameters which are mainly: –Loads – Pressure –Ground surface roughness – Temperature – Aircraft roll If basic braking recommendations are applied: Overall tire DMC impact is likely to be small Straight line rolling: 20% to 30% Maneuvering : 10% to 20% Touch down: 20% to 30% Braking: 20% to 40% Tires
12
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 12 Other operating costs consideration Brakes Braking Energy (10 6 J / wheel) REV MAXREV IDLENo REV CONF FULL (30/40)91814271833 CONF 3 (15/20)102015332040 Increasing the approach speed and/or using Rev Idle will lead higher brake temperature Example of brake energy difference depending on the approach speed and the use of reverse : A300-622 Autobrake LO Slight increase Multiplied by 1.5 Multiplied by 2
13
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 13 Other operating costs consideration Brakes In general carbon brake life is affected by –Carbon brake wear –Carbon brake oxidation Catalytic oxidation Thermal oxidation
14
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 14 Other operating costs consideration Carbon brake wear is mainly affected by: –Number of brake applications Not linked to the approach conf or the use of reversers Brakes: Effect on Carbon Brake wear
15
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 15 Other operating costs consideration –The brake temperature Messier - Bugatti Honeywell-ALS BF Goodrich 0 Wear rate 80 Indicated temperature C 250150315500 Optimum brake temperature range is still compatible with such operations Brakes: Effect on Carbon Brake wear Carbon brake wear is mainly affected by:
16
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 16 Other operating costs consideration Thermal oxidation is temperature and time related: –Repetitive high temperature occurrences –Long duration of carbon exposure to high temperature Brakes: Effect on Carbon Brake thermal oxidation Thermal oxidation leads to severe brake damage (disk rupture, etc) or loss in braking efficiency Premature brakes removal
17
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 17 Other operating costs consideration Increased approach speed Higher brake energy is necessary to stop the aircraft Rev Idle instead of Rev max Poor sharing of brake energy between reversers and brakes Depending on flight crew braking management, brake oxidation could be drastically increased Brakes: Effect on Carbon Brake thermal oxidation
18
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 18 Other operating costs consideration To minimize negative effect on the brakes the following could be considered: –Restrict the application of such procedure to runway where Autobrake LO can be used and is actually used. –Do not override the autobrake to shorten the landing distance. –Respect basic Airbus SOP recommendations: Delay the brake fans selection for 5 minutes (or at the gate) if turn-around permits. Avoid prolonged parking brake application on hot brakes. Brakes: General guidelines
19
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 19 Content General considerations Fuel economy estimation Additional considerations: Other operating cost considerations Operational consequences Pro and Cons: Summary Conclusion
20
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 20 Operational consequences Approach in CONF 3: Higher pitch attitude May increase the number of alert triggering by the Flight Data Monitoring software Impact on tailstrike margins –Tailstrike margins are reduced (except for the A321 aircraft) but, for example, roughly corresponds to: –5 to 6 degrees on Single Aisle Aircraft family –7 to 8 degrees on Long Range Aircraft family Tailstrike margins remain comfortable
21
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 21 Operational consequences Potential increase in runway occupancy time and block time Additional brake cooling time: could be limitative in case of short turn around-time Must be taken into account for operations Use of reversers at Idle:
22
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 22 Content General considerations Fuel economy estimation Additional considerations: Other operating cost considerations Operational consequences Pro and Cons: Summary Conclusion
23
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 23 Pro and Cons: Summary Landing in CONF 3 Use of Idle reverse thrust Tires DMC Thrust reversers DMC Tailstrike margins Brake wear Brake oxidation Brake cooling time Runway occupancy time The economics vary a lot from one airline to another but pro and cons can be summarized as follows: Fuel economy Noise reduction FOD
24
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 24 Content General considerations Fuel economy estimation Additional considerations: Other operating cost considerations Operational consequences Pro and Cons: Summary Conclusion
25
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 25 Conclusion –Airbus recommendation is: To maximize safety margins in normal operation, Airbus SOP still recommends to approach in CONF FULL and to use MAX thrust reverse for landing. For economics, provided runway length and conditions are favorable, landing in CONF 3 and/or use of idle reverse thrust can be considered. No REV landing not recommended System Safety Assessment based on the fact that reversers are deployed at each landing No real benefit in term of fuel economy
26
© AIRBUS S.A.S. All rights reserved. Confidential and proprietary document. April 2007Landing in CONF 3 - Use of reversersPage 26 Conclusion When applying such procedure, to minimize induced negative effect, the following could be considered: Restrict the application of such procedure on runway where Autobrake LO can be used and check dispatch conditions. Do not override the autobrake to shorten the landing distance Pay particular attention on brake fans use Good Dispatcher and Flight Crew awareness is necessary Clear Airline policy has to be defined for: - All aircraft types - All considered runways
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.