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Thread: B738, EEC altn./assumed temp
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Old 17th Sep 2012, 09:31
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de facto
 
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Can you guys tell me why it's not possible to use the assumed temperature reduced thrust method with EEC's in alternate mode?
Simple, Boeing says NO,not allowed.I guess its because you will use performance restrictions to calculate your vspeeds and you dont have ass temp tables provided for that condition.


Also, I read that during a takeoff in soft alternate mode the engine may windmill during takeoff, increasing N1 by as much as 7 %.
You dont take off using soft alternate mode,you will be using the Hard Alt mode following your DDG.
N1 may increase during roll out but yet again if you follow your DDG, a weight penalty will occur,reducing your N1 for the weight,keeping it below your max thrust rating N1 limit,even with 7 perc roll increase.(26k for actual conditions)
What does the EEC do during normal conditions to stop this from happening?
It uses the great tool of Autothrottle and its computer.
Last edited by de facto; 17th Sep 2012 at 09:38.
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