Autorotation is Controlled Flight

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Clearing up something that might not be apparent to non-pilots.

Yesterday, I got the following tweet in my notifications from someone who had never tweeted at me before:

This was mind boggling to me. I replied:

His response came later in the day:

He was referring to one of my YouTube videos, R44 Helicopter Autorotation Practice. That video records my practice session with CFI Trevor Hale at Wenatchee Pangborn Memorial Airport early one July 2019 morning. What I’d hoped to accomplish with the video is to take some of the mystery out of autorotations for non-pilots and to take some of the fear of practicing and dealing with engine failures for helicopter pilots. The video shows the two of us sitting in the cockpit while I simulate one engine failure after another by cutting the throttle and disengaging the drive system from the rotor system. The only thing keeping the blades spinning is me doing what I’ve been trained and tested to do for the past 20 years: full (or almost full) down collective to reduce drag and pitch to maintain optimum airspeed and rotor RPM while flying to a suitable landing spot.

What I guess a lot of people still don’t get is that when a pilot performs an autorotation, she has full control of the helicopter and is flying the helicopter. The pilot does not become a passenger, as she would if she lost control. She can move the helicopter in any direction except up, steering it as necessary to make the spot.

Now let’s say a helicopter has a ballistic parachute system at the top of the rotor mast as this person on Twitter suggests. Can someone explain to me why a pilot might deploy this parachute, thus giving up control of the aircraft, in the event of an engine failure when autorotation makes it possible to stay in control all the way to the ground? I’m not seeing it.

Some of you might know that Cirrus airplanes have this a ballistic parachute system built in. It’s not designed for engine failures, however. It’s designed for situations when the pilot cannot control the plane to a safe landing. All pilots, regardless of what they fly, are trained to deal with engine failures during various stages of flight. If there’s nothing physically wrong with the aircraft’s flight controls or surfaces, there’s really no reason to rely on a parachute to get you to the ground safely. Start the appropriate emergency procedure and fly the aircraft to the ground.

And let’s be honest now: how often do engines fail? Bored one afternoon? Go to the NTSB’s web site and read a bunch of accident reports for airplanes and helicopters. It’s all there. How many of them were caused by engine failures? How many of them were caused by mechanical issues at all? And how many were caused by pilot error?

It isn’t engine failures that pilots should be fearing. It’s their own stupidity. (And yes, I’m a poster child for that.)

So I posted my response, challenging him to explain what I was apparently missing:

I hope I educated him and any others who don’t quite understand what happens if a helicopter engine quits and the pilot does what she’s trained to do.

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9 thoughts on “Autorotation is Controlled Flight”

  1. With over 10000 helicopter hours, I have done practise (and for real) touch down autos. No damage in the practise ones, but cut through the tailboom of a real one when the engine suddenly died without previously misfiring or spluttering at low level (crop spraying).. Landing good, but the machine (Bell 47) slid forward a yard or so dug the skids into soft ground causing the rotor mast to tip forwards, and the retreating blade flexed down cutting the tail drive shaft and two top rear boom tubes.
    Bit embarrassing as there was no fuel left in the tanks due to float level system being malajusted. Fuel guage read 1/4, but actual contents just fumes.
    Walked away from that one, but was highly pissed at the maintenance guys. Yes, my fault for not dipping the tanks, but I only had a mile to go to refuel.

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    • Just a quick note here… if you haven’t been watching my YouTube videos, I hope you’ll give them a try. I’d really love it if someone who is experienced would comment once in a while to counteract some of the non-pilot “experts” who seem to weigh in on too many things they know absolutely nothing about, thus spreading misinformation. http://youtube.com/c/flyingmair

      Unless you’re there already? If so, never mind. (My head is really full of stuff right now; juggling too many projects at once.)

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    • Thanks to John for his honesty.
      We learn so much more from these real world accounts than we do from routine testing of skills where the examiner cuts our power over some convenient surface such as ten acres of smooth asphalt.
      I know four GA pilots who have faced sudden real-life total power loss emergency landings.
      All survived but in three cases the aircraft was too damaged to be economically repairable.
      The one pilot I know who landed his aircraft undamaged had the good luck to land on short Spring pasture. He aimed for a very small flattish field. He had to jink over some power cables then duck under low phone wires as he touched down. Cows he had avoided came to congratulate him.
      This is the equivalent of an aviation miracle. Best not to expect too many of those…

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    • I’ll tell you this: You’ll also hear it when the engine “skips a beat.” I had that happen to me just once in my old helicopter about halfway through its life. I think a piston misfired or something? I don’t know, but I heard it and immediately had both hands tight on the controls waiting to go down. But kept running and I never heard it happen again. Still, I’m pretty sure I didn’t imagine it and I hope I never hear that again.

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  3. Back in the 80s, the UK CAA cleared Lycoming engines to run on premium motor fuel (mogas). This represented a big saving over Avgas fuel (about £12 per hour). All went well to start with, but after some 100 hours of operation, I got intermittent misfiring, especially at full throttle (low level crop spraying). A few days later, the misfire developed into a loud clanking noise and big reduction of power. No choice but to land immediately. On inspection, the push rod tubes of 2 of the 6 cylinders were bent in the middle by about 1 inch.
    We recovered the helicopter (bell 47 G4a) by road, and on strip down two exhaust valves were jammed open.
    The mogas was unleaded, yet the engine needs a small content of lead to lubricate the exhaust valve stems (avgas 100LL). Nobody mentioned that!
    Shortly afterwards the clearance to use unleaded mogas was revoked!

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    • I was told that in a pinch I could put premium gas in my R44 but it wasn’t recommended. The reason: it needed that lead. So your story doesn’t surprise me.

      My R22, years ago, developed a sticky valve that actually stuck hard when I was parked up on top of a mesa on some property I owned back then. I could hear the difference when I started up and wisely shut down. Had to bring a mechanic up from Wickenburg (a 2.5 hour drive) and he had to bang on it with a hammer to get it unstuck. I have photos somewhere. What made me feel good is that he agreed to fly back with me rather than make the long drive back with my future wasband. I figured that if he was flying with me, it must be okay.

      Reply ↓

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