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Thread: Derate vs ATM
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Old 12th May 2018 | 18:58
  #16 (permalink)  
Lascaille
 
Joined: Jan 2015
Posts: 453
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From: Jupiter
Originally Posted by PAG
Thousands of flight are operated every day using this certified app, so I think it's reliable.
Can you please explain again your calculations, what do you mean by double derate ?
Sorry, I meant derate to 22k. I was hoping to see three sets of results all for the same n1 but with the n1 achieved through three different means:

​​​​​1. 22k derate but no assumed temp (n1 let's say 94%)
2. 24k derate and assumed temp (n1 also 94%)
3. No derate, assumed temp (n1 also 94%)

With the same n1 the distances should be fairly similar unless different assumptions are being made for one particular condition. This would better show the odd one out.

I still don't really see how the all engine go distance can sensibly be longer than the inop go distance unless a different v1 was used for each calcuation, which seems quite misleading as the results are going to be for one takeoff with one v1 speed.
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