How to Deal With Engine Failure in the Hover
If there is a warning of engine failure in the hover (usually a horn or other auditory sign), lowering the collective would not be sensible. If you were to do this from a normal 4 to 5-foot hover height, the helicopter would simply end up crashing to the ground. Instead, you should simply hold the collective position, then gradually raise the collective a little to cushion the landing as the helicopter gently settles on to the ground. You will also need to apply the right pedal, because without an engine the helicopter will tend to yaw (turn) to the left due to the turning effect of the tail rotor. This is actually the most obvious sign of engine failure in the hover. Of course, you will also need to hold the cyclic position steady.
During a hover/engine failure situation, it is important that the pilot learn to realize what is happening and not to react by trying to get on the ground as quickly as possible, i.e. by lowering the collective. This tends to be instinctive without prior practice of the correct technique. In helicopter flight training, you will learn to deal with engine failure when the instructor closes the throttle, at first with a warming, and later possibly without advance notice.
What About if the Engine Fails at Low Level?
If the engine fails when flying above 500 feet, a normal auto-rotation is possible and should not be too difficult. The same applies to engine failure in a normal hover. However, if the engine fails when in a high hover or at low level, such as when taking off, things are much more difficult. Basically all you can do is try to put the helicopter into a normal auto-rotation, but there is very little time available. This is one of the reasons why helicopter pilots are constantly told to either hover at a low level or fly at above 500 feet and spend as little time as possible getting from the first of these to the second. But of course sometimes both high hovering and low level flying are necessary, so it is essential to be wary and aware of the possible – though slight – dangers of this type of flying.
Engine Failure in a Helicopter
It should be emphasized yet again that engine failure is very rare. Modern day helicopters have very reliable engines and many, if not most, pilots go through a lifetime without ever experiencing a real-life engine failure outside of training and practice, in the hover or at any other time. I’ve been one of those, and I sincerely hope that trend continues!
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