Control surface failure

[UnAnswerd]

Most airplanes can be flown without a rudder, but is it safe to say, that 100% failure of either the elevator or aileron control system will result in certain death?

 

[banned username 2]

Most airplanes can be flown without a rudder, but is it safe to say, that 100% failure of either the elevator or aileron control system will result in certain death?

Last time I was at 900EX recurrent, on the last sim session we were goofing around and the instructor was trying to see if he could kill us... We successfully landed with simultaneously jammed ailerons (in the neutral position) and a jammed elevator (neutral position)... Used rudder and stab trim and landed on a 5,000 ft long runway, got it stopped and stayed on the pavement, even maintained centerline...

Can it be done? Yes... Would I want to do it in real life? Not so much...

 

[Big Duke Six]

I would say the elevator is the more critical component of the two, but even then, thrust and trim can be used in the event of elevator failure as was stated above. The loss of ailerons could be overcome by differential thrust and rudder of course.

I am curious though: How bad would the dutch roll be if you lost your rudder in a swept-wing aircraft? Would it be potentially life-threatening?

Anyone?

 

[mar]

An extreme example

I admit this goes beyond the original question but remember that Japanese 747 that lost all hydraulics when the aft pressure bulkhead severed all lines in the tail?

The thing oscillated about for several turns before finally crashing into a mountain peak.

Bad news.

 

[Twotter76]

I once got a three system (thats all of them) hydraulic failure in the sim and was able to to successfully land the aircraft using only differential thrust and elevator trim (which is all you have left on a CRJ is you lose all three systems - no flight controls). There was no tendency for dutch roll. However if any of them had been jammed in other than a neutral position (unlikely) it would be very difficult to control.

 

[domyalex]

There was a case of a DHL A300 a couple of months ago in Irak; it took a hit from a man portable SAM on its wing. It lost all hydraulic circuits and the wing was badly damaged. The crew managed to understand how their "new" A300 flew and landed safely at the departure airport. No injuries nor damages to other perons/properties.
I think it was even posted here on the board togheter with a .ppt presentation.
Way to go!

EDIT: oh, here it is: http://forums.flightinfo.com/showthread.php?t=25361&highlight=iraq+A300

 

[groundpointsix]

What about United 232? Granted that wasn't the most successful landing, but it was far better than it could have been. On the flip side of the coin, the Alaska MD-80 accident a couple years back didn't end so well. I would say it depends on too many variables to make a blanket statement about flight control failures and certain death.

 

[Mr. Cole]

I practiced control surface failures last time I flew with Rich Stowell. If the aileron jams you convert it into a slip by going with opposite rudder. If the rudder jams you convert it into a slip by turning to the other side with aileron. As the others have already mentioned, if the elevator fails you can use power and trim.

Dave

 

[fastandlow]

Never give up, at least until the noise stops. In the past, I've taught students that there are many redundant ways to control a plane. Rudder/aileron, flaps/power/pitch trim/elevator. Heck, if you're quick enough, you can even defeat some uncontrolled up and down pitch with severe bank and turning. It's better than closing your eyes and screaming all the way down!

Couple of instances to ponder - I know of an RV-4 that was landed with the pilot reaching back and flying with the aft stick (fwd stick linkage failed), an acro plane that had an elevator stuck down who rolled, climbed inverted for a period and managed to bail out. Not to mention the transport jets who've managed to fly with minimal flight control. got a buddy who used to work with McDonnel-Douglas who said the F-15 could be flown to some degree with thrust manipulation only.

lots of conditions apply. But loosing one, maybe two flight control systems isn't as bad as loosing the Jesus bolt on a helicopter!

 

[VNugget]

How about the F-15 that lost all of a wing save for 2 feet at the root? He spun, recovered, then slowed down, spun and recovered again, and landed at something in the neighborhood of twice his normal approach speed.

HUD video of the midair

Narrative and picture

 

[avbug]

It's been said before and bears saying again...

Fly the biggest piece home.


You are defeated at exactly the moment you surrender. Until then, it's only a challenge.

 

[TrafficInSight]

I admit this goes beyond the original question but rememberthat Japanese 747 that lost all hydraulics when the aft pressurebulkhead severed all lines in the tail?

The thing oscillated about for several turns before finally crashing into a mountain peak.

Bad news.

They didn't just lose hydraulics, the aft pressure bulkhead rupturing blew the vertical tail off the airplane.

 

[qmaster3]

What about United 232? Granted that wasn't the most successful landing, but it was far better than it could have been. On the flip side of the coin, the Alaska MD-80 accident a couple years back didn't end so well. I would say it depends on too many variables to make a blanket statement about flight control failures and certain death.

Considering they had only thrust. I would call United 232 a successful landing.

 

[mar]

Holy crap! I had no idea.

...the aft pressure bulkhead rupturing blew the vertical tail off the airplane.

I first read about that crash back in '88 or '89 or thereabouts. I guess I missed that part.

That would certainly aggravate the situation.

 

[PropsForward]

Read several accounts on NTSB of small piper warrior types loosing elevator control and being able to land them using trim and power.

I would think the real issue on a small airplane is if the failue has created some adverse drag (like the SR22 that had an aileron become partially disconnected).

 

[Frmr Avro Drvr]

Last time I was at 900EX recurrent, on the last sim session we were goofing around and the instructor was trying to see if he could kill us... We successfully landed with simultaneously jammed ailerons (in the neutral position) and a jammed elevator (neutral position)... Used rudder and stab trim and landed on a 5,000 ft long runway, got it stopped and stayed on the pavement, even maintained centerline...

During one of my sim sessions in the Saab 340, the instructor jammed the left aileron channel (Captain) and the right elevator channel (FO). We split the controls and my partner (the Captain) had the left elevator and thottles and I had the right aileron and rudder.

It was a trick but we got it down in one piece. Of course the sim was set with no wind or bumps. Don't know if I would want to do it in real life but it was a fun exercise.

 

[groundpointsix]

Considering they had only thrust. I would call United 232 a successful landing.

Yeah, I guess I worded that poorly. I only meant that it was less successful than a landing in a functional airplane. Excellent landing considering the circumstances. Sorry for the confusion.