Flight Control Failures?

So that is two posts for ruder failure. I guess the aileron guys aren't still around.
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Orange Anchor said:
Reminds me of the shop board that posts labor rates.
$75/hr if we do it
$100/hr if you watch
$150/hr if you help

The guy who does the annual on my Swift is, like the airplane, getting on in years so I get to twist into the cramped spaces at no extra charge. And you learn quickly the unwritten rule of airplanes assembled in those days.

1) if you can see it, you can not reach it.
2) if you can reach it, you can not see it.
3) before you can get to the part you want to work on, you have to removed X parts to get at it. The smaller the part you need to work on, the more parts have to be removed.
4) the smaller the part, the longer the part number.
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That is just funny.
 
Douglas said:
So that is two posts for ruder failure. I guess the aileron guys aren't still around.
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Yeah....that is what I was thinking. I still haven't been able to find too many reports on it and if resulted in an accident, it's gonna be in the database.

Well, as I have said before, when it's my time, it's my time! :)
 
Douglas said:
I guess the aileron guys aren't still around.
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Yeah, that is a frightening thought. My primary instructor showed me how I could use the doors on a 150 to maintain directional control if I ever lost the ailerons.

Hopefully it will never come to that.
 
matt152 said:
Yeah, that is a frightening thought. My primary instructor showed me how I could use the doors on a 150 to maintain directional control if I ever lost the ailerons.

Hopefully it will never come to that.
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Doesn't work very good in a Cherokee....you know with the one door and all. :)
 
Although it's probably not considered a "small" plane for the purposes of your discussion - the flight controls are all conventional pulleys and cables - control yoke direct to the flight controls - no hydraulics involved. ZV5481, the BE1900 crash in CLT in 2003 was attributed to loss of pitch control - the airplane flew for several legs after coming out of maintenance, but for the accident flight it was determined that it was loaded past the aft CG limit and the elevator was rigged where the pilots didn't have full down elevator authority. I believe the investigation found that had the elevator been rigged properly, the pilots probably could have flown the aircraft even with the CG past the aft limit. The final report is on the NTSB major investigations page - and it resulted in everyone changing their average passenger weight from the 170/175 to 184/189/190/195.

After the accident the training department started jamming the elevator in the simulator, and it's not pretty, but you can "fly" around the pattern to land with no elevator control. I hope I never have to do it in real life, but at least in the simulator I have a 66% success rate in landing the 1900 with no elevator control.

Well anyway the point is that you're probably not going to experience a flight control failure, but more likely where you won't have full control authority of an elevator or aileron, etc.
 
Failure of one aileron is not bad unless it is jammed up or down. The ones that I have seen (due to cable breakage) centered back up and the other aileron still controlled the roll. There was a guy that flew a comedy act at Oshkosh last year that "loses" one of the ailerons and continued to fly the show.
 
t-cart said:
Failure of one aileron is not bad unless it is jammed up or down. The ones that I have seen (due to cable breakage) centered back up and the other aileron still controlled the roll. There was a guy that flew a comedy act at Oshkosh last year that "loses" one of the ailerons and continued to fly the show.
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That is a good point. I went back all the way to 1980 on the NTSB website and couldn't find one fatal accident in a Cherokee that involved flight control failure. So, it does appear to be a fairly bulletproof system (with correct maintenance of course). I guess my paranoia about "loss of control" is pretty unfounded. I have never really been "afraid" of engine failure, but not being able to control the airplane, we'll, I don't like that idea very much!!!
 
I agree that the one thing I'm paranoid about is control surface failure. Engine failure, and you still have control. Controll failure and now your in a helicopter without a tail rotor.
 
If I recall correctly standard procedure in the 172 for an elevator failure is trim straight & level for 70 knots then bring it in using power only for pitch control.

For an aileron failure I imagine you just look for a wide runway generally aligned with the wind and make it work. Land it in a little bit of a crab if you have to. Loss of rudder I bet would be pretty similar.

On my first flight with a new instructor he made me take off and fly around for about 10 minutes using nothing but rudder and trim. Interesting experience.
 
TallFlyer said:
If I recall correctly standard procedure in the 172 for an elevator failure is trim straight & level for 70 knots then bring it in using power only for pitch control.

For an aileron failure I imagine you just look for a wide runway generally aligned with the wind and make it work. Land it in a little bit of a crab if you have to. Loss of rudder I bet would be pretty similar.

On my first flight with a new instructor he made me take off and fly around for about 10 minutes using nothing but rudder and trim. Interesting experience.
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Rick Reuss perchance? He does full patterns in without controll surfaces using the doors and trim and the rudders, then he fails everything except doors and you become a weight shift machine for a little while (not in the pattern, just out in the practice area). The problem is that on anything heavier than a 172 this becomes impractical, as the doors are too far away to reach and actually cause something to happen.

Control surface failures can be a relative non-event. However, what I was really worried about at ace was a weakened floor due to corrosion between CAMP inspections followed by a heavy palate (sp?) crushing the floor in severe turbulence and pinning the control cables in place, and potentially in an other than neutral position. Same fear in the 207, but not as much because we rarely carry really heavy stuff. Max floor loading on the 1900 IIRC was 100lbs/sq ft. However, if the palate breaks (which I've seen happen in rough rough skies) and the giant drillbit/hulking monstrosity/awkwardly shaped difficult to strap down POS/etc rests entirely on the floor their good be an issue. Now, again IIRC the floor loading is stressed to the aircraft limits, but still I've been in some pretty terrible mountain wave coming over the hills, and frankly, it always had me worried.
 
I have had an elevator trim cable snap on me in flight. It was in an arrow just after takeoff when the student complained of having a really stiff trim wheel. Well I started playing with it and noticed there was a really tough spot to turn it through. I moved it back and forth a few times and then it just snapped. Luckily it was in a pretty neutral position and the landing wasn't too difficult. It had apparently been like that for a while and no one else renting the aircraft had squawked it.
 
i had an arrow trim tab wire snap on me too, the trim was in the full forward position, landing was interesting but uneventful. If you think about it, GA aircraft that fly a lot are things like flight school aircraft, they require inspections every 100 hours, and they inspect the wires, if now every 100 hours all control cables and push rods are inspected yearly in the annual inspection. If certain tolerances aren't met, the part is replaced, even if it looks alright to the untrained eye.
 
Pilotforhire587 said:
i had an arrow trim tab wire snap on me too, the trim was in the full forward position, landing was interesting but uneventful. If you think about it, GA aircraft that fly a lot are things like flight school aircraft, they require inspections every 100 hours, and they inspect the wires, if now every 100 hours all control cables and push rods are inspected yearly in the annual inspection. If certain tolerances aren't met, the part is replaced, even if it looks alright to the untrained eye.
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Very true...but sometimes thing are missed, or as I discovered doing research, things break prematurely, even when you are trained to detect discrepancies.

As I was flying back from LR this weekend and my wing was getting heavy (fuel burn) I wondered how that could be complicated with a jammed aileron cable. Could be interesting. I guess it's a good discussion since most of the "emergency" discussions revolve around "common issues" like engine or electrical failure. When I do SIM checks in the C-5, I like giving the "seldom studied" EPs to see how they react. Usually the first thing out of their mouth is something like "What?!? That never happens!!!". Well, it's in the book for a reason!!! :)
 
GalaxyIFE said:
So in regards to the little airplanes, how common are flight control failures? The cable systems are obviously very simple but I would think that there are more failures than there seem to be. I did a search on NTSB and found very few accidents that were attributed to flight control failure. Maybe I am just a little paranoid, but it seems like that the failure of a cable, or just the simple cable coming loose from a bell crank would be more common than it is.
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Had a P-3 a couple of years back in Nav, they forgot to reattach the aileron bellcrank, at 80 knots the yoke did a hard snap to the left, aborted, found the bellcrank not attached.

I also lost the elevator boost on a P-3 out of Washington in 2003. Next to impossible to move the elevator with no boost.
 
If your realy that worried about ti, come down to my neck of the woods. We teach control surface failures. The course was developed by two master CFI's, one is a Master Aerobatic CFI. Check CP Aviation/emt
 
mjg407 said:
I also lost the elevator boost on a P-3 out of Washington in 2003. Next to impossible to move the elevator with no boost.
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So did you just fly it with trim? Or do the next-to-impossible feat of flying it with the yoke like that?
 
We snapped an elevator cable in the twin beech once, I was in the right seat on the radios at the time. It happened on the takeoff roll a second or two after he brought the tail off the ground, then the yoke just went all the way forward to the stop. We were going pretty fast but still on the runway so we closed the throttles and rolled it out. It was a non-event really but a few seconds later and we would have been airborne.
 
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