PPRuNe Forums - View Single Post - Air North Brasilia Crash in Darwin (Merged)
Old 25th Mar 2010, 21:37
  #188 (permalink)  
Josh Cox
 
Join Date: Dec 2009
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But, 400 RPM (stated by AerocatS2A) for a windmilling prop sounds a little too low. This value leads me to suspect that there is some form of lock in the propeller - to prevent the fine pitch angles that give the high windmilling RPM and consequent enormous drag.
With both Garrett (-10 and -11U) and Pratt (-41, -42, -34, -67 and -114), when the engine stops working, oil pressure is lost/drops very considerably in normal operation, the props will feather over 20-30 seconds due to loss of oil presssure.

This is something you should know instinctively.

When a prop is feathered, it just about always still rotates a little inflight, every configuration is different.

No multi engine aircraft that I know of when the powerplant fails, the prop will move to the fine position ?.

ace from space also said flight-idle for the engine failure simulation on the EMB-120. His was an interesting account and revealed that the aircraft was virtually out of control. How would it have gone if the prop was windmilling?
As a pilot with a META, this is, and how power reduction stops yaw is a part of the VMCA demonstration, done at a safe altitude.

I have never experienced a prop ceased in fine pitch, but FI on either type presents a huge amount of drag, I believe the engine is not driving the propeller in either case, so what is ?.

All the turbine aircraft I have flown will still climb with one engine at FI and the other producing max power above V1 on T/O and inflight.
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