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Old 10th Sep 2018, 15:47
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extricate
 
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Dubai 39 deg TO and Flat Rated Engines

Hi there,

I was reading about this article:

Temperature Inversions and Takeoff Performance Calculation | Flight

In the article above, it talked about GE-90's flat rated temp (Tref) as ISA+15. In Dubai's case, it;s 30 deg. With an OAT of 39 degrees, it will exceed the Tref (as mentioned in the article), thus leading to a decrease in thrust in order to maintain the EGT limits.

I was playing around with the calculations and with the following inputs:
OMDB
Rwy: 12R
Wind: 140.10
OAT: 40 deg
QNH: 1010
TOW: 350T (close to max)

Performance calculated TO takeoff with flaps 5. When I changed the OAT to 41 deg, no calculations allowed. Thus, if i'm faced with a low-level temperature inversion after liftoff, i'm screwed. Any thoughts on this?
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