getting to grips with aircraft performance 如何掌握飞机性能 1(46)

曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

Before A : Return After B: continue
BA
Net Flight Path 2,000 ft 2,000 ft Net Flight Path
Figure D6: Continuing Point (B) Located Before the No-Return Point (A)
Divert
Aft
e
r
B
:
c
on
ti
nu
e

Before A : Return
AB
2,000 ft
2,000 ft
Net Flight Path  Net Flight Path
Figure D7: Continuing Point (B) Located After the No-Return Point (A)
2.2.3. Diversion Airfield

“JAR-OPS 1.500
(a) The net flight path must have a positive gradient at 1,500 ft above the aerodrome where the landing is assumed to be made after an engine failure.“ (Figure D8)
The route study must indicate the different possible en route diversion airfields associated with the various diversion scenarios. The net flight path gradient should be positive at least at 1,500 feet above the airport where the landing is assumed to be made. For that purpose, fuel jettisoning can be considered, when the system is available.

Moreover:
“JAR-OPS 1.500 (c)(4) The aerodrome where the aeroplane is assumed to land after engine failure must meet the following criteria:
.  
The performance requirements at the expected landing mass are met

.  
Weather reports or forecasts, or any combination thereof, and field condition reports indicate that a safe landing can be accomplished at the estimated time of landing”

Alternate airports must be clearly specified in the dispatch or flight release, and must meet the prescribed weather minimums for the approach category. If these minimums are not met, the associated diversion procedures are no longer possible.

2.3. Twin Engine Aircraft
2.3.1. 60 Minute Rule

“JAR-OPS 1.245
(a) Unless specifically approved by the Authority […], an operator shall not operate a two-engined aeroplane over a route which contains a point further from an adequate aerodrome than the distance flown in 60 minutes at the [approved] one-engine-inoperative cruise speed”.
When at least one route sector is at more than 60 minutes’ flying time, with one engine inoperative from a possible en route diversion airfield (Figure D9), the airline needs  specific approval, referred to as ETOPS1 approval. ETOPS is dealt with in an Airbus-specific brochure entitled: “Getting to Grips with ETOPS” and will, therefore, not be detailed in this manual.

2.4.  Four Engine Aircraft
2.4.1. 90 Minute Rule

“JAR-OPS 1.505
(a) An operator shall ensure that at no point along the intended track will an aeroplane having three or more engines be more than 90 minutes, at the all-engines long range cruising speed at standard temperature in still air, away from an aerodrome at which [landing] performance requirements are met, unless it complies with [specific rules]”.
1 ETOPS = Extended range with Twin-engine aircraft OPerationS
　
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：getting to grips with aircraft performance 如何掌握飞机性能 1(46)