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Old 3rd November 2014 | 12:28
  #42 (permalink)  
Gysbreght
 
Joined: May 2014
Posts: 193
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From: In thin air
I've no reason to doubt the authenticity of the gradient information provided by FE Hoppy. We differ in the explanation for the decrease with temperature.


Many aircraft exhibit this, perhaps not always as pronounced as the E190. As explained by Keith Williams, elementary flight mechanics indicate that it is not caused by the increasing TAS, so it must be caused by decreasing thrust. A possible explanation is that the thrust of the uninstalled engine is flat-rated but installation effects, such as bleeds and the power absorbed by the accessory gearbox, increase with increasing ambient temperature, so that the installed thrust decreases.

Last edited by Gysbreght; 4th November 2014 at 07:59. Reason: Vilas changed to FE Hoppy
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