Note 2: The fuel consumption with L/G down is approx. three times the average consumption for that AUW.
Decision Management
Below 100 Kt.
The decision to reject the take-off may be taken at the discretion of the captain, according to the circumstances.
Note: The speed of 100 kt is not critical and was chosen in order to help the captain make his decision and avoid unnecessary stops from high speed.
Above 100 Kt and below V1
Rejecting the take-off is a more serious matter particularly on slippery runways and could lead to a hazardous situation when speed is close to V1. The decision to reject the take-off should only be taken for a very few causes the main ones being:
1. Fire warning or severe damage,
2. Sudden loss of engine thrust,
3. Conditions of malfunctions where there are unambiguous indications the aircraft will
not fly safely.
Note 1 : Nose gear vibration should not lead to an RTO above 100 Kt.
2:.Standby ASI failure should not lead to an RTO above 100 Kts.
3. Both PFD speed scales failed at 100 knots is cause for reject
Experience has shown that rejected take-offs were sometimes hazardous even though the performance was correctly calculated, based on flight tests.
This may be due to the following factors:
- Delay in initiating stopping procedure.
- Tyres are damaged.
- Brakes worn or not working correctly, initial temperature higher than 150 deg C
- Brakes not fully applied.
- Runway friction coefficient is lower,
- Error in gross weight / T/O speeds determination,
- Runway line up not considered.
Since above 100 kt, rejected take-off becomes a serious action which may lead to a hazardous situation, in particular as speed approaches V1, be "Go-minded". After a reject no attempt should be made to clear the runway until it is absolutely certain that an evacuation is not necessary and that it is safe to do so. In the event of an unserviceable auto-brake, the captain must ensure spoiler Deployment and (Thus Improving Braking action) simultaneously reduce the thrust and depress both pedals fully.
Minimum stopping distance can only be achieved if the brake pedals are kept fully depressed until the aircraft comes to a stop, however if the Auto brake has engaged in Max mode, it should not be disengaged.
REVERSERS Full reverse thrust must be used, if available. If sufficient runway length is still available at the end of the deceleration it is preferable to reduce reverse thrust -- passing 80 kt., but idle reverse thrust must be maintained till the aircraft comes to a stop -- (Refer to STANDARD OPERATING PROCEDURES chapter -- LANDING ) 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：Airbus ABNORMAL/EMERGENCY PROCEDURES 空客非正常/紧急程序(7)
