Originally Posted by A37575
When the instructor closes the throttle against the aft stop it not only simulates a windmilling condition but it is actually windmilling and that means lots of drag.
Which is what happens if you have a total engine failure.
If the student faffs around going through all the "mixture up - pitch up - power up etc drills he must remember the windmilling prop ensures the aircraft will not only lose speed rapidly but also go downhill. Which is precisely why twin engine aircraft have a prop feathering system to remove windmilling drag.
Yep, once again what actually happens.
While the exact manifold pressure and associated RPM to simulate zero thrust will vary with conditions, it is vital that the instructor applies zero thrust within a few seconds of pulling back the throttle to its stops to simulate the engine failure.
Can't agree with this at all, if after pulling the throttle back to simulate failure, the instructor sets zero thrust quickly, what is the point of the student doing the drills?
The way it was done when I did my inital multi was throttle back to simulate failure, when I got to the 'feather' part of the checks i would tap the correct pitch lever (to indicate that's where I would feather) and my instructor would set zero thrust. If you just set zero thrust quickly, you are teaching the student that the situation is going to magically get better after a short time, which it won't untill they get the thing feathered. What good is that?
Because speed/altitude/directional control and climb performance is so critical during simulated engine failure immediately after take off it becomes a serious flight safety issue if the instructor delays setting zero thrust while waiting for the student to go through all the drills up to when he would normally press the feathering button or pull back the pitch lever into feather.
Don't even slightly agree. I don't think the instructor should set zero thrust until the student is ready to 'feather' the failed engine. If things get too out of shape, push the throttle forward and you have normal 2 engine climb to complete a circuit and try again.
As long as the instructor gets some power into the simulated dead engine literally within seconds of pulling back the throttle in the first place it doesn't matter too much if the zero thrust setting is not exactly correct - as long as the setting is not LESS than zero thrust. Far better to err on the cautious side.
Still don't agree, and yes zero thrust is a pretty rough figure.