Reduced Thrust Examples
Airbus Model A340-541
And example of the conservatism inherent in the use of the assumed (flexible) temperature method of reduced thrust calculation.
Conditions A340-541 RR TRENT553 Sea level OAT = 15°C 11824ft runway
Actual airplane weight = 372t permits assumed (flexible) temperature of 40°C
PARAMETERS Actual temp is 15°CFLEX temp is 40°C Actual tempis 40°C Margin
V1 (kt IAS/TAS) 154.6 / 155.1 154.6 / 161.6 - 6.5 kt TAS
EPR at V1 1.264 1.264 0
Thrust at V1 (lbs/eng) 38386 38386 0 lbs
VR (kt IAS/TAS) 163.3 / 163.8 163.3 / 170.8 - 7 kt TAS
V2 at 35ft (kt IAS/TAS) 174.9 / 174.0 174.9 / 181.4 - 7.4 kt TAS
Far field length (ft) 10955 11824 869 ft
Accelerate-stop distance (one engine out) (ft) 10233 11165 932 ft
Accelerate-go distance (one engine out) (ft) 10495 11319 824 ft
Accelerate-go distance (all engines) (ft) 10955 11824 869 ft
Second segment gradient (%) 4.03 4.04 0%
Second segment rate of climb (ft/mn) 710 740 - 30 ft/mn
Lineup Distance Charts
90 degree runway entry 4-I ABI-3 180 degree turn on the runway 4-I ABI-4
Lineup Distance Charts
Lineup corrections should be made when computing takeoff performance anytime the access to the runway does not permit positioning of the airplane at the threshold. The data contained in this appendix is based on the manufacturer's data for minimum turn rad consistent with the turning conditions shown in figure 2 and 3. Operators can use the data in this appendix to develop lineup corrections appropriate to any runway run geometry. However the use of data in this appendix does not supersede any requirements that may be already be in place for specific regulatory agencies. If further assistance is required, the operator should contact the appropriate manufacturer and regulatory agency to assure compliance with all applicable regulations.
Definitions of terms
The takeoff distance (TOD) adjustment is made based on the initial distance from the main gear to the beginning of the runway since the screen height is measured from the main gear, as indicated by distance "A" in Figure 1. The accelerate-stop distance (ASD) adjustment is based on the initial distance from the nose gear to the beginning of the runway, as indicated by distance "B" in Figure 1.
When determining a runway lineup allowance, the characteristics for maneuvering each airplane model onto each runway should be used in calculating the required corrections. For example, runways with displaced take off thresholds or ample turning aprons should not need further adjustment as shown in Figure 2, runways that require a 90 degree turn-on taxiing on the runway with a 180 degree turn at the end, Figure 3 and 4, may require a lineup adjustment. This appendix contains the appropriate minimum lineup distance adjustments to both the accelerate-go (TOD) and accelerate-stop (ASD) cases that result from a 90 degree turn onto the runway and a 180 degree turn maneuver on the runway. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：TAKEOFF SAFETY TRAINING AID(8)
