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Thread: Derate vs ATM
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Old 19th May 2018, 09:12
  #47 (permalink)  
john_tullamarine
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with the ATM only, the crew can increase the thrust but it is not required to do so to meet the performance standards.

Not only is increasing the thrust setting not required (other than, perhaps, in situations of impending ground contact), it is potentially hazardous unless you have practiced the sequence well in the sim. A thrust increase puts a very high cognitive and hand-eye-leg co-ordination workload on the manipulating pilot. Very easy to get into PIOs and, depending on the speed schedule and how good the engine is (ie potential for a thrust overswing) the potential is there for a lateral loss of control.

Many years ago, I was involved with a post fatal investigation where the most likely precipitator to the departure leading to ground impact was just this situation ...

If you REALLY must increase thrust, please do it slowly and steadily so that you have a better chance to keep the feet dancing in time with the music.
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