Can You Survive Elevator Loss?

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Garavar

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Garavar
Having a debate with a friend of mine who is training to be CFI.

On a 172/182 if the LEFT elevator came off mid flight could you survive it and land? I mean completely off, just ripped off, not jammed or flapping.

I say Left in this hypothetical instead of Right because the Elevator Trim tab is on right. Thoughts?
 
There is a stark difference between reality and possibility. In this case I’ll say maybe but there are so many factors involved with cg, speed control and much more.
 
Garavar said:
Having a debate with a friend of mine who is training to be CFI.

On a 172/182 if the LEFT elevator came off mid flight could you survive it and land? I mean completely off, just ripped off, not jammed or flapping.

I say Left in this hypothetical instead of Right because the Elevator Trim tab is on right. Thoughts?
Click to expand...


Yes.
 
Garavar said:
Having a debate with a friend of mine who is training to be CFI.

On a 172/182 if the LEFT elevator came off mid flight could you survive it and land? I mean completely off, just ripped off, not jammed or flapping.

I say Left in this hypothetical instead of Right because the Elevator Trim tab is on right. Thoughts?
Click to expand...
Yes, it's happened.
www.pilotsofamerica.com

Team AeroDynamix Collision

I hope I embedded the photo correctly. Collision in the Team AeroDynamix show today at the Tuscaloosa Regional Airshow. The pilot did a hell of a job getting it back down to the taxiway away from the crowds.
www.pilotsofamerica.com www.pilotsofamerica.com

Team Aerodynamix: Planes Land Safely After Mid-Air Collision | Aero-News Network

RV-6, RV-8 Touched During Air Show Performance Normally when there is a mid-air collision that involves one of the aircraft losing part o| Published: Thu, Apr 02, 2015 | Aero-News Network
www.aero-news.net
www.kathrynsreport.com

Team Aerodynamix: Van's RV-6, N722DK and Van's RV-8, N8JL: Accident occurred March 29, 2015 at Tuscaloosa Regional Airport (KTCL), Alabama

NTSB Identification: ERA15LA172A 14 CFR Part 91: General Aviation Accident occurred Sunday, March 29, 2015 in Tuscaloosa, AL Aircraft: ME...
www.kathrynsreport.com www.kathrynsreport.com
 
Trivia Points Bonus - They have developed a program to auto throttle an airliner to control decent and landing should elevator and aileron controls become compromised / non functioning.

BTW - I'm assuming that missing half of the elevator doesn't mean that what's remaining is jammed in a non neutral position.
 
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Garavar said:
Having a debate with a friend of mine who is training to be CFI.

On a 172/182 if the LEFT elevator came off mid flight could you survive it and land? I mean completely off, just ripped off, not jammed or flapping.

I say Left in this hypothetical instead of Right because the Elevator Trim tab is on right. Thoughts?
Click to expand...
You mean like Godzilla just came out of the ocean and ripped off the elevator? Probably not.
 
Garavar said:
Or a collision, faulty screws etc.
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You need to look at how that elevator is mounted. There are two hinges, both pretty stout, and the inboard end has a tube welded to a bracket that is riveted to the elevator's inboard rib. On the inboard end of that tube is welded a flange, and that flange mates with the elevator bellcrank and FOUR bolts go through the flange, bellcrank, and the flange for the right elevator, and then nuts are installed and torqued. You'd have to have a lot of stuff fail for an elevator to fall off. In fact, you'd need the whole affair to be really badly corroded, and then you'd have other problems like the whole horizontal stab coming loose or rusty cables breaking. Or the stab's spar failing and the stab folding downward. Now you'd really be dead.
 
Dan Thomas said:
You need to look at how that elevator is mounted. There are two hinges, both pretty stout, and the inboard end has a tube welded to a bracket that is riveted to the elevator's inboard rib. On the inboard end of that tube is welded a flange, and that flange mates with the elevator bellcrank and FOUR bolts go through the flange, bellcrank, and the flange for the right elevator, and then nuts are installed and torqued. You'd have to have a lot of stuff fail for an elevator to fall off. In fact, you'd need the whole affair to be really badly corroded, and then you'd have other problems like the whole horizontal stab coming loose or rusty cables breaking. Or the stab's spar failing and the stab folding downward. Now you'd really be dead.
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He was asking hypothetically. Not whether or not you could survive the event that would actually be involved to make it happen. Just wants to know if a 172 will fly with only the right elevator.
 
Well then, the answer to the question, hypothetically speaking, is “Maybe”.
 
No problem. The plane would be slower to respond but otherwise not a big deal.

Can you fly with one aileron? Yep.

One flap would be better left retracted.
 
Yes, if you have a BRS installed. Just pull the chute.
 
Different but related (I posted this previously) but I noticed this distortion on pre-flighting the Pawnee recently. Weird thing is that I flew it the day before without a problem and we're all having a hard time figuring out how it happened. The mechanic couldn't explain it but did say that it was "unexpectedly easy" to bend it back. (And, no, we didn't fly it again and have ordered a new one.)

It was still firmly attached to the bellcrank and the right elevator was normal.

EL3.jpg
 
dbahn said:
Different but related (I posted this previously) but I noticed this distortion on pre-flighting the Pawnee recently. Weird thing is that I flew it the day before without a problem and we're all having a hard time figuring out how it happened. The mechanic couldn't explain it but did say that it was "unexpectedly easy" to bend it back. (And, no, we didn't fly it again and have ordered a new one.)

It was still firmly attached to the bellcrank and the right elevator was normal.

View attachment 120837
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Has to be the sleeve, right? Fixed it yet?
 
Yes.
You can also survive and steer the plane if the ailerons & rudder are immobilized. Unlatch both doors, pop them open just a tad then latch them so they stay "open". Push either door open against the slipstream wind and it shoves the nose the opposite direction.
 
This is why you always wear a parachute and have fire extinguishers strapped to your legs.
 
Stewartb said:
Has to be the sleeve, right? Fixed it yet?
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Not sure what the “sleeve” is but the torque tube was twisted and one side of the trailing tubular structure was bowed.
 
dbahn said:
Different but related (I posted this previously) but I noticed this distortion on pre-flighting the Pawnee recently. Weird thing is that I flew it the day before without a problem and we're all having a hard time figuring out how it happened. The mechanic couldn't explain it but did say that it was "unexpectedly easy" to bend it back. (And, no, we didn't fly it again and have ordered a new one.)

It was still firmly attached to the bellcrank and the right elevator was normal.
Click to expand...
I'd cut the cover off that elevator and get a close look at the structure. Easy to bend suggests metal failed somewhere. You are lucky you caught it before it gave way completely, or you might have been testing the OP's question IRL.
 
Ed Haywood said:
I'd cut the cover off that elevator and get a close look at the structure. Easy to bend suggests metal failed somewhere. You are lucky you caught it before it gave way completely, or you might have been testing the OP's question IRL.
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The mechanic did that and determined that it could not be made airworthy. So it’s gone to the trash.
 
I don't see why it wouldnt, as long as nothing else was damaged. I'd guess there'd still be enough lift/stability with one elevator and the remaining piece of the empanage. Probably want to be careful with a slip though, as the airflow being reduced over the remaining elevator could prove catastrophic.
 
Garavar said:
Having a debate with a friend of mine who is training to be CFI.

On a 172/182 if the LEFT elevator came off mid flight could you survive it and land? I mean completely off, just ripped off, not jammed or flapping.

I say Left in this hypothetical instead of Right because the Elevator Trim tab is on right. Thoughts?
Click to expand...

I am assuming the horizontal stabilizer on both sides are intact. In that case, applying elevator just on the right side will cause the airplane to yaw, but it might be possible to counteract that yaw with rudder. It's hard to say at what speed you will lose complete elevator authority. An unexpected pitch drop at 100 ft off the ground could be catastrophic. I would pick a super long runway and fly the approach at high speed until touchdown.
 
AlleyCat67 said:
Not completely off but close

American AA-5 Traveler, N5880L: Accident occurred January 19, 2021 at Leesburg Executive Airport (KJYO), Loudoun County, Virginia

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final repor...
www.kathrynsreport.com www.kathrynsreport.com
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The video of this event is harrowing. There was not enough elevator authority to properly raise the nose and it is amazing that the aircraft managed to crunch down relatively safely ("landed" would be charitable in this case).
 
It's easy to forget that the elevator and stabilizer, together, form a wing. Losing an elevator means losing a huge chunk of the wing on one side, so just how effective is the remaining stabilizer? It might mean the the other side has to provide ALL the downforce and control, and would the aircraft designers make the horizontal tail any bigger than necessary to be safe? Extra metal is more weight. Extra area is more drag. Extra build time is more cost.

Then there's the question of the strength of that stabilizer. Mechanics like me who have had that whole affair apart know that the front spar of the stab is very light and is held to the fuselage bulkhead there by two bolts and nuts. That spar is notorious for cracking when pilots push down on the tail to turn the airplane on the ground. Cessna forbids that in the service bulletin published on the subject in the 1990s. The rear spar takes most of the aerodynamic loads and is stronger, but its mounting points are a lot closer together since that aft bulkhead is right at the end of the tapered fuselage. What happens when the load on the stab and elevator become so unbalanced, with the surviving side providing all the downforce in the approach and landing, including making up for the lack of it on the failed side? Does that aft spar do it without trying to torque itself off that bulkhead?

Scenarios like this are ridiculous. You're better off spending your time learning about the airplane's structures and systems and why regular, thorough inspections are not expensive at all when put into context with inflight failures.
 
Yes, maybe.

I know of a Pilatus Porter that broke a jack screw. It was able to land on throttle and remaining controls only. No elevator.

I built my Fisher FP303 to be able to climb and descend on throttle only, letting the stick flop loose. Just rudder and throttle. I built it so theoretically, if I lost elevator, or stick control, I could still land it. Or at least a reasonable facsimile of a landing.

So, it depends.
 
The Porter uses a jackscrew to actuate the elevator? You sure about that? Or is it a jackscrew-actuated stabilizer trim system?
 
It could have been and probably was the trim system. He said it nosed over hard. If they hadn't started at 13k feet they wouldn't have been able to control it. They barely did as it was. Two very experienced pilots.

My point was it was a non/mal-functioning elevator. They were able to land it with throttle and what they had left.
 
Flyxaos said:
My point was it was a non/mal-functioning elevator. They were able to land it with throttle and what they had left.
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A malfunctioning trim is not a malfunctioning elevator.

FAR 23.677

(d) It must be demonstrated that the airplane is safely controllable and that the pilot can perform all maneuvers and operations necessary to effect a safe landing following any probable powered trim system runaway that reasonably might be expected in service, allowing for appropriate time delay after pilot recognition of the trim system runaway. The demonstration must be conducted at critical airplane weights and center of gravity positions.

I take that to mean that the trim system must not be powerful enough to overpower or override the pilot's elevator inputs.

I would presume that the Swiss laws are similar. That's where the Porter was built.
 
I've had a jackscrew break on a PA12 floatplane. The fatigue break was inside the threaded housing until with a large enough trim adjustment it wasn't. Then you're just stuck with that amount of trim for the rest of the flight, but it remained flyable.
 
MRC01 said:
Yes.
You can also survive and steer the plane if the ailerons & rudder are immobilized. Unlatch both doors, pop them open just a tad then latch them so they stay "open". Push either door open against the slipstream wind and it shoves the nose the opposite direction.
Click to expand...

Seat track allows for CG pitch changes too
 
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