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Old 21st Dec 2021, 14:28
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Lantirn
 
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Originally Posted by john_tullamarine
For obstacles, you run the standard net flight path analysis and adjust TOW
What is the gradient of the standard net flight path analysis assuming no obstacles?

Also I wrote "will diverge by 0.8% for all the takeoff profile by the obstacles" obviously meant minimmum, by the net.

Originally Posted by john_tullamarine

Your statements are all correct. Yes the net is 1.6% on 2 engine a/c and yes it clears obstacles by 35ft

No, quite incorrect. First the 1.6% is OEI, NOT AEO as might be inferred from your comment. The 1.6% is a WAT limit and knows naught about obstacles. The NFP obstacle analysis, which will keep the RTOW at, or below, the WAT limit is the thing which looks after the obstacle clearance.

I thought takeoff segments were only for N-1 engines. Thats why I wrote that for 2 eng a/c, it is 1.6%.

I am not a perf engineer neither a perf instructor, but anyway these are always interesting topics that I like to learn from well educated guys

Originally Posted by john_tullamarine
(c) operational climb requirements, such as SIDs or other ATC directed requirements.
Sorry to kindly ask, but what these have to do with single engine performance? SIDs and ATC requirements are for all engines ops.

Last edited by Lantirn; 21st Dec 2021 at 19:01.
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