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Old 3rd November 2014 | 06:39
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Owain Glyndwr
 
Joined: Jun 2011
Posts: 476
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From: West of Offa's dyke
@FE Hoppy

I'm with Gysbrecht. If you plot out the gradients listed you will find they vary directly with temperature. TAS however varies with the square root of temperature.
There is nothing in Keith Williams equations to link gradient with TAS - on the contrary, Equation 1 excludes any such relationship.
Checking the net for data on the E190 speeds I found that V2 at a given TOW is constant EAS over the flat rating temperature range.
So if it isn't TAS and it can't be drag at a constant EAS then it must be something in the way the engine is flat rated.

Last edited by Owain Glyndwr; 3rd November 2014 at 06:41. Reason: spelling
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