Rotor inertia

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I am working on my rotor rating in an R22 and have read that upon
power loss I have less than 2 seconds to get the collective full down
in order to preserve rotor speed. Is it realistic to expect to be
able to recognize the problem and react fast enough in a normal
flight situation?

Second part of the question is, what is the time factor for the R44?

-- Kimball Forrest, May 10, 2007


Do people handle engine failures in the R22? Sometimes yes and sometimes no. Certainly students who are prepped by an instructor are able to get the collective down in time 99 percent of the time. In real life, though, the record is less encouraging. Many early failures were due to carb ice and there were some fatal accidents, though most pilots managed to do some sort of autorotation.

In the R44 you have closer to 4 seconds, about the same as with a JetRanger.

Not too many helicopter accidents, at least in certified aircraft, are related to power loss. I would say that the R44's big extra margin of safety is more in training than in point-to-point cruising.

-- Philip Greenspun, May 10, 2007

Good comment. Over the years during fixed wing training it has been repeated many times that typically a fixed wing pilot takes 2 -3 seconds to fully recognize and begin to react to an engine failure. There is that moment of surprise, then disbelief, then trouble shooting then finally recognition and action. I suppose the low rotor horn would shorten that reaction time but it seems that the reflex would have to be nearly perfect to prevent too low rotor rpm at least in the R22.

As we all know in fixed or rotor wing the best way to prevent power loss is use carb heat, sufficient fuel (without water) and oil.

-- Kimball Forrest, May 11, 2007

Just a note on the R44 and engine failures. It is my understanding, that the R44 has never had an engine failure reported in it's history. I wanted to share that, and if anyone has contradictory information, please share.

-- Ronda Johnson, June 12, 2009