Fail-safe settings for control surfaces

[Dave Reaville]

Hi Keith

Now that's a great idea..... say a two to three second lock-out on neutral (with throttle cut) then some type of "containing" manoeuvre such as a slow spin. This would address short term signal loss and give you the safety needed with a full blown TX failure. You could call it PCM Fail-Safe II for marketing purposes.... hope the producers are listening err... reading :-) 

Dave

  ----- Original Message ----- 
  From: Keith Black 
  To: discussion at nsrca.org 
  Sent: Tuesday, May 17, 2005 12:33 PM
  Subject: Re: Fail-safe settings for control surfaces


  I have my settings to lock everything in place and drop the engine to idle. When you hear the engine drop (or notice no pull if there are other noisy planes close by) a quick wiggle of the wings lets you know if you're locked out of if your engine is dead. In fact, often it's possible to know you're locked out before you hear the engine because you can instantly feel the plane not responding. We don't realize it all the time, but we're always making tiny adjustments and you can tell immediately when the plane doesn't respond, even in level flight.

  My thought is that I don't want to *cause* a crash by throwing the controls into a configuration that could take me from a controlled attitude to a dangerous attitude if I get just a short signal interruption. 

  I think all of the points made are good ones, there's no perfect answer. I'm just hopeful each time I fly that I don't "loose it". I think the most important thing is the throttle cut. Beyond that there are pluses and minuses to both freezing all surfaces and putting it into a spin. Maybe the ideal solution is a system that would freeze the surfaces for lockouts of only a second or two, and then the ole' autopilot fly in circles approach for longer lockouts.

  Keith
    ----- Original Message ----- 
    From: Rick Kent 
    To: discussion at nsrca.org 
    Sent: Tuesday, May 17, 2005 12:58 PM
    Subject: Re: Fail-safe settings for control surfaces


          You're one of the luckier ones then. What was the plane's attitude at the time of lockout?
          Point to ponder: Do you think you'd have noticed that "I ain't got it" revelation sooner with the surfaces set to hold or set to a spin? The engine throttle-back could be misconstrued  as a flameout, so I don't think that's too reliable an indicator of lockout by itself.
          Just curious. I would think it depends what you were doing with the controls at the time of lockout.

          Rick


          -------Original Message-------

          From: discussion at nsrca.org
          Date: Tuesday, May 17, 2005 12:28:33 PM
          To: discussion at nsrca.org
          Subject: Re: Fail-safe settings for control surfaces

          Rick,
              My Prophecy went into failsafe (idle and hold for all other channels) and came out after about a second ( it seemed like an hour ).  I suspect interference but was not able to find any one month later using the district 6 scanner.
          Paul
          ----- Original Message ----- 
          From: Rick Kent 
          To: discussion at nsrca.org 
          Sent: Tuesday, May 17, 2005 9:08 AM
          Subject: Re: Fail-safe settings for control surfaces


                It would be interesting to see statistics on how often a plane comes out of failsafe and the pilot regains control before meeting with Mother Earth. It's never happened for me, but admittedly, I don't use the feature often. Had two sport airplanes go into lockout when I did use it, and I watched both spin in.
                I agree a spin recovery isn't the easiest thing to execute down low when you're in a panic, but I'd venture to say it would buy you more time than being in a vertical dive while in lockout would--IF the receiver recovers signal in time. I think it just comes down to dumb luck really, in what attitude/altitude the plane is in when the lockout occurs. The question is what are the odds that your plane would only go into lockout in level flight vs. the middle of a snap, roll, inverted dive, etc. Assuming worst case scenario, i.e., no signal recovery, the spin at least puts the plane back on the field so you can find it, and hopefully the spin would serve to somewhat lessen the descent speed at impact. Maybe a flat spin would be better in that regard.

                My luck with such things dictates that it doesn't really matter what I plan for--the plane's going in, and hard.

                Rick
               
               

         
                 
         
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