Old 17th Aug 2015, 07:48
  #53 (permalink)  
Virtually There
Join Date: May 2007
Location: Australia
Posts: 190
Take-off torque is transient in that, once set, you will first see an increase due to ram-air, and then torque will start to decrease as you gain altitude (for the same power lever setting). Normal take-off procedures take this into account.

One thing that hasn't been addressed yet is that extended operation at higher ITTs - even within take-off and climb parameters - will reduce the serviceable life of a PT6. This is one reason why some operators prefer to set take-off torque slightly below maximum (assuming enough runway) with slightly reduced climb-out performance.
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