Would you want this on your aircraft?

Please read the OP.

  • Yes

    Votes: 8 11.3%
  • No

    Votes: 63 88.7%

  • Total voters
    71

MachFly

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MachFly
I've seen this feature on one aircraft last week (I don't want to say which aircraft in order to avoid any bias thoughts), and I'm interest to know how many of you would want this on your aircraft. This aircraft had an autopilot which would automatically take control (regardless whether it's on or off) and try to return the aircraft to normal flight if you accede the bank angle of 45 degrees, pitch up more than 12 degrees, or pitch down more than 17 degrees. In order to disengage that feature you can do one of three things, continuously hold the autopilot disconnect button, pull the autopilot circuit breaker (which is located in a very hard to reach spot), or disable it after each start up in the autopilot settings.

So would you want this feature on your aircraft?
Please vote in the poll.


I personally hate the idea of such a thing, but that's just me.

P.S. The aircraft was a single engine piston used for GA purposes.
 
Absolutely not.

If you have flown in turbulence the thought would never cross your mind again. :no:
 
I would have loved to have such a system on the Decathalon. That airplane was always trying to depart straight and level flight.
 
I'd prefer to have a little more control over it but sure, why not? If launching into severe VMC, just turn it off.
 
Just to clarify, it's not 45 degrees of control deflection, but actual 45 degrees of bank. At least as far as I understand, I haven't actually flown with it.

Also you can try to overpower the autopilot...
 
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That's one of them envelope protection bright futures
Like it or not, chances are, it's going to do good to the overall safety record.
 
That's one of them envelope protection bright futures
Like it or not, chances are, it's going to do good to the overall safety record.

I wouldn't mind such system if it was 75 degrees of bank and 50 degrees of pitch, but with 45 degrees of bank you can't even do a standard steep turn. And the airplane I'm talking about was a rental from a flight school, used mainly for pilot training.
 
Systems that assume control and land the plane at a nearby airport when required are inevitable. The only question is what is the time table.

Would I get this for my experimental? Not now. Too weird.
 
Un-uh, they would never accept any device that would infringe on their overhead breaks.
If it were such a good idea experimental APs would already have it. ;)
 
If it were such a good idea experimental APs would already have it. ;)

Pfft. My first airplane was experimental and had certain bells that my present ride doesn't (one of the first SkyViews flying, VP electric sys, two speed trim etc - N787FL is google'able). While I'm all for some "bright future" things in E-AB, you've got to admit that the experimental world isn't all peaches and cream. Way too many people think they are the first ones to come up with such a grand idea - and as a result there's a gazillion E-AB's out there that I wouldn't touch with a ten foot pole. Seriously though, winglets are a good idea. How come you don't have any?
 
I wouldn't mind such system if it was 75 degrees of bank and 50 degrees of pitch, but with 45 degrees of bank you can't even do a standard steep turn. And the airplane I'm talking about was a rental from a flight school, used mainly for pilot training.

Well, that's details. I bet by the time that's operational, it'll have a brain of its own and will know when you are loosing the control of the situation.

Heck, I remember Bell 429 sim session a couple of years back - hydraulic system 1 failure. The switch is 3-position - "sys 1 off" - "both on" - "sys 2 off". Guess what happens if you throw the switch to "sys 2 off"? Everybody dies? Nope. The thing tells you "Hydraulic system selector switch is in incorrect position" or something along these lines, and doesn't do anything. I bet it also sends an e-mail to the boss with a timestamp and "there's a retard driving me" note.
 
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Nope, I do like the blue button idea though. I'd rather have to opt in than opt out......
 
What if I was flying along fat dumb and happy and suddenly need to yank and bank to avoid a bird? Helo? Falling piano?
 
What if I was flying along fat dumb and happy and suddenly need to yank and bank to avoid a bird? Helo? Falling piano?

The logic of such systems would prevent it from overpowering you. You'd be supposed to yank and bank while holding a button, but even if you didn't disconnect the AP, the system should (and would if I was the one designing it) agree to whatever it is that you were doing while beeping at you and flashing colors.
 
The logic of such systems would prevent it from overpowering you. You'd be supposed to yank and bank while holding a button, but even if you didn't disconnect the AP, the system should (and would if I was the one designing it) agree to whatever it is that you were doing while beeping at you and flashing colors.

Too weird, complex, and touchy. If I can over power it so can turbulence.
 
Too weird, complex, and touchy. If I can over power it so can turbulence.

You can overpower any autopilot servo, you know that, right?
From my present ride's checklist Garmin GFC700 AP

7 FMS setup ..................................COMPLETED 7
AUTOPILOT TEST
DISCONN press, check electric trim not working
AP ON, check overpowering servos
DISCONN press, check AP off
8 Autopilot test ..............................COMPLETED 8
 
MachFly

What you mentioned is called Flight Envelope Protection. This function is already available in some large aircraft embeded in the Flight Control Computer FCC. When I was working on this for the B7J7 program the issue was not how hard would be to disconnect but how easy would be to go into the free mode. Granted that some airplanes can not be flown without the FCC involved but this is not the case for GA planes. I had so many autopilots and trim servos runaway that I am glad they were easy to disconnect. All these systems are at least tripple redundant with a voting scheme. The cost is a lot higher than a GA new plane.
 
MachFly

What you mentioned is called Flight Envelope Protection. This function is already available in some large aircraft embeded in the Flight Control Computer FCC. When I was working on this for the B7J7 program the issue was not how hard would be to disconnect but how easy would be to go into the free mode. Granted that some airplanes can not be flown without the FCC involved but this is not the case for GA planes. I had so many autopilots and trim servos runaway that I am glad they were easy to disconnect. All these systems are at least tripple redundant with a voting scheme. The cost is a lot higher than a GA new plane.

I completely understand why you'd want one/need one in an airliner, but not in something with 6 cylinders and a prop.
 
I would not want this in the pattern around the airport. If I'm not in the patters, I would think a 2 axis autopilot would be just as good.
 
As long as I practiced and could disengage in a false positive situation I would prefer to have an advanced autopilot.
 
You can overpower any autopilot servo, you know that, right?
From my present ride's checklist Garmin GFC700 AP

7 FMS setup ..................................COMPLETED 7
AUTOPILOT TEST
DISCONN press, check electric trim not working
AP ON, check overpowering servos
DISCONN press, check AP off
8 Autopilot test ..............................COMPLETED 8

http://www.ntsb.gov/doclib/reports/2009/AAR0906.pdf
 


There have been plenty of accidents caused by autopilots and electric trim runaways.


Envelope Protection sounds great, right up until the air data computer gets a faulty signal from the AHRS and it kills you because it caught you off guard.

Not to mention this kind of system, if installed on type certificated products, would likely not be MMEL'able and unairworthy if malfunctioning.
 
There have been plenty of accidents caused by autopilots and electric trim runaways.
As someone who was damn near killed by a malfunctioning A/P in a 172 years ago, I can tell you that "can be overridden" depends on whether everything works as it should.
 
I love autopilots. Sounds a bit overkill but sure I'd take it. You can always turn it off. I see nothing to be gained experience wise by hand flying straight and level for hours at a time.
 
I don't have a problem with autopilots in general either, and in fact plan to have it in my plane. Our club 172 needs constant hands-on to maintain level flight (probably a rigging issue), and it's a pain in the rump to not be able to pull out a chart or the AFD without starting a slow roll to the right. But the idea of a device that can decide on its own to start making control inputs, whether you want it to or not... no way.
 
You can always turn it off.


IF you're lucky. One NTSB report I read on a Cessna 525 pitch trim runaway was caused by the PC board controlling the system and A/P disconnect did nothing, nor could it be overidden. The single pilot could not find the circuit breaker and fight to keep the nose down at the same time. Everyone died.
 
I don't have a problem with autopilots in general either, and in fact plan to have it in my plane. Our club 172 needs constant hands-on to maintain level flight (probably a rigging issue), and it's a pain in the rump to not be able to pull out a chart or the AFD without starting a slow roll to the right. But the idea of a device that can decide on its own to start making control inputs, whether you want it to or not... no way.


I would spend the money to rig the airplane properly, not on gadgets to mask the problem.
 
Both my primary and secondary autopilots already have this feature, and have since 2004. Not sure what the big deal is.
 
Just to clarify, it's not 45 degrees of control deflection, but actual 45 degrees of bank. At least as far as I understand, I haven't actually flown with it.

Also you can try to overpower the autopilot...

And if I'm making a 60 deg steep turn to avoid traffic?

It may make checkrides interesting as well. Bank to 46 deg instead of 45? Oh well.
 
I would spend the money to rig the airplane properly, not on gadgets to mask the problem.
So would I, if I owned that airplane outright. It's a club plane, and while I've suggested we have it properly rigged there is not a snowball's chance in Oklahoma of it ever seeing an autopilot installed. Retrofitting a certified A/P in a 172 would certainly not be the answer to a mis-rigged control surface, and would be so expensive I wouldn't even want to think about it.

I am, however, building an RV. It will be rigged for hands-off flight, and will have an autopilot installed -- one that I know I can both disable and override in the event that it malfunctions.

Just to clear up any misunderstanding.
 
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