Another Hypothetical - When would you purposefully land gear up?

[TMetzinger]

In another thread, we discussed the loss of roll control and what pilots might do to handle that emergency.

The discussion in this thread is a mirror to that - imagine what sort of scenario(s) would lead you to consider landing a retractable gear airplane on a runway with the gear retracted. Since landing gear up is (aside from the engine and belly damage) generally a fairly benign event, then it seems to me that any situation with a higher risk to life would call for landing gear-up.

I'll start - loss of yaw control and significant winds not aligned with the runway. It might be better (if all you have is pitch and roll) to land under control on the upwind side of the runway and take advantage of the reduced stopping distance and increased energy dissipation instead of landing on wheels and not being able to maintain control for a longer period of time and a slower energy decay.

Asymmetrical gear deployment, or nose gear not aligned with the runway. I'm not sure that our gear is as stout as the airliner that had the nose gear misalignment a few years back and ground down the nose wheel, and I'm not sure I'd want to bet passengers on it.

I'm starting these discussions because it's my belief that the best time to work an airplane problem is in the comfort of your chair on the ground, with the airplane manuals handy, no pressure, etc. If you can think about this stuff now, you can have lots of situations "pre-solved" when you get in the airplane. Kind of the way NASA and the airlines have checklists and predetermined procedures for even low probability events.

 

[kevin47881]

I would purposefully land gear up if the gear would not drop.
Is that too obvious an answer?

 

[SkyHog]

About the only time I'd ever land gear up is during a partial gear deployment in an airplane prone to flipping.

Any other time, I'd rather land with the feet out. I can't imagine landing gear up intentionally in any situation where the gear is functioning properly.

 

[AdamZ]

Tim I dont' think your going to know in a standard GA SEP retract ie Lance, Comander etc that your nose wheel is not aligned but given begnine enviormental conditions I think if only one gear was down I'd still try to put it down with the gears extended. The damage with only the nose gear down would ostensibly be limited to tail strike and probably wingtip damage but would perhaps save the engine. If your in a twin then with only one main down your at least saving one engine.

I'd belly it in to a runway and you did specify runway if it was a turf or unimproved or soft runway. I'm still thinking about why I'd belly it in to a paved runway. Perhaps and I emphasis perhaps I would if it was a very short paved strip and my throttle and mixture cables had broken or stuck full open. You could always kill the engine with the fuel shut off valve but I have no idea how long that would take to kill the engine. I don't think I'd want to be rocketing it in a 1400' strip with no mixture to kill or throttle to pull back and only breaks to stop me.

 

[ScottM]

I would land gear up on purpose if ditching. That would help prevent you from flipping over during the landing.

 

[Ken Ibold]

I would land gear up on purpose if ditching. That would help prevent you from flipping over during the landing.

Analyses of ditching accidents show that fixed gear aircraft are no more likely to flip than retracts. While your position has a certain common sense appeal, the data does not bear out the validity of it.

 

[ScottM]

Analyses of ditching accidents show that fixed gear aircraft are no more likely to flip than retracts. While your position has a certain common sense appeal, the data does not bear out the validity of it.

Do you have some of that data that you can share?

I ask because that is what is currently being taught by the Coast Guard and is in their aviation training books.

 

[TMetzinger]

As far as landing gear up if you think any of the gear might not be down and locked or down, locked, and aligned...

Which has a greater risk of hurting the occupants?

Landing in a controlled flat attitude with the gear retracted, or landing with the gear in whatever configuration it is and having a gear leg collapse and losing control of the airplane?

I can hear Ron now - "It will vary from airplane to airplane", and of course, he's right, some airplanes might be very resistant to flipping over or catching fire or whatever if a nose wheel or one MLG wheel collapses. Others (maybe those with tip tanks) might be worse off.

From what I've seen of gear-up landings, when the airplane is landed slowly and under control with the gear up on a runway, it's a walk-away event. When a gear collapses on roll-out, it may be less likely to be a walk-away event.

 

[TMetzinger]

Do you have some of that data that you can share?

I ask because that is what is currently being taught by the Coast Guard and is in their aviation training books.

I agree - everything I've seen published says to leave the wheels up when landing on the water (especially in an amphibian!)

 

[Pi1otguy]

Do you have some of that data that you can share?

I ask because that is what is currently being taught by the Coast Guard and is in their aviation training books.

http://www.equipped.com/ditchingmyths.htm
(Its a repost if an Aviation Safety article)
Myth #5

Unfortunately, the accident records shed no useful light on this controversy. Pilots often don't remember whether they extended gear and/or flaps; they don't recall if they landed with the swells or upwind or crosswind. Even if they do remember, this detail often doesn't make it into the accident summary.

A little inconclusive, but the punch line is that generally you've be able to exit after a ditching.

 

[TMetzinger]

http://www.equipped.com/ditchingmyths.htm
(Its a repost if an Aviation Safety article)
Myth #5


A little inconclusive, but the punch line is that generally you've be able to exit after a ditching.

Sorry, that just tells me that ditching is a traumatic event, after which your memory is not reliable, and as one who's ridden the USCG's dunker more times than I liked, I fully agree. I note that current policy for CG airplanes is to ditch with the wheels retracted.

 

[Pi1otguy]

Sorry, that just tells me that ditching is a traumatic event, after which your memory is not reliable, and as one who's ridden the USCG's dunker more times than I liked, I fully agree. I note that current policy for CG airplanes is to ditch with the wheels retracted.

It'd make little sense to ditch with gear down in a retract. With gear up I'd assume the deceleration would be lower but flipping danger is currently unproven. But considering the plane and cargo is likely a total loss, does it really matter considering most people survive the ditching?

 

[Lance F]

Maybe if ONLY the nose gear extended, I would retract it and land on the belly. Otherwise I would leave down whatever was down.

Edit: See post 16

 

[tonycondon]

From what I've seen of gear-up landings, when the airplane is landed slowly and under control with the gear up on a runway, it's a walk-away event. When a gear collapses on roll-out, it may be less likely to be a walk-away event.

depends on the collapse. I certainly walked away from my nose gear collapse with no worries. I would think about landing all up if one main gear wouldnt extend, but if the nose gear was faulty I would (and did) land with the gear out. I tend to like symmetry of forces. However, ive seen several videos of SE Cessnas landing with only one main gear extended and they were able to land fine and keep the wingtip off the ground until pretty low speed, and with minimum spinning involved.

 

[tonycondon]

Maybe if ONLY the nose gear extended, I would retract it and land on the belly. Otherwise I would leave down whatever was down.

really? Ive seen several examples of cessna retracts where the mains wouldnt come out but the nose was able to extend and lock due to airloads. The landings were successful, and of course a wingtip dropped but usually at pretty low speed.

 

[Lance F]

really? Ive seen several examples of cessna retracts where the mains wouldnt come out but the nose was able to extend and lock due to airloads. The landings were successful, and of course a wingtip dropped but usually at pretty low speed.

On thinking further I will change my position. If any combination of wheels came down (proven locked or not), I would leave em down. My objective would be the softest touchdown I could accomplish and keep the wings level as long as possible.

 

[TMetzinger]

This has been good - it appears that the collective wisdom so far is that landing on whatever gear you've got, while maintaining control is not significantly more dangerous than landing on the belly.

 

[SkyHog]

This has been good - it appears that the collective wisdom so far is that landing on whatever gear you've got, while maintaining control is not significantly more dangerous than landing on the belly.

I think the thought process (at least mine) is that gear up or down probably won't effect controllability enough to warrant a belly landing.

 

[flyingcheesehead]

I'll start - loss of yaw control and significant winds not aligned with the runway. It might be better (if all you have is pitch and roll) to land under control on the upwind side of the runway and take advantage of the reduced stopping distance and increased energy dissipation instead of landing on wheels and not being able to maintain control for a longer period of time and a slower energy decay.

I disagree - Metal on concrete isn't really going to stop you that fast. I'd bet you could stop faster with heavy braking, and landing with the wheels down would also give you some control via differential braking after touchdown.

Asymmetrical gear deployment

Most definitely!

I'm starting these discussions because it's my belief that the best time to work an airplane problem is in the comfort of your chair on the ground, with the airplane manuals handy, no pressure, etc. If you can think about this stuff now, you can have lots of situations "pre-solved" when you get in the airplane.

Amen to that... Thanks!

Tim I dont' think your going to know in a standard GA SEP retract ie Lance, Comander etc that your nose wheel is not aligned but given begnine enviormental conditions I think if only one gear was down I'd still try to put it down with the gears extended. The damage with only the nose gear down would ostensibly be limited to tail strike and probably wingtip damage but would perhaps save the engine. If your in a twin then with only one main down your at least saving one engine.

I'd be more concerned with a potential loss of control resulting in spinning/flipping/whatever with asymmetric deployment. Forget saving the engines or any other part of the airplane - It belongs to the insurance company.

I'd belly it in to a runway and you did specify runway if it was a turf or unimproved or soft runway. I'm still thinking about why I'd belly it in to a paved runway.

There's supposed to be LESS damage on a paved runway than on a grass runway... Though I'd sure like to know where that knowledge comes from. Ken?

Perhaps and I emphasis perhaps I would if it was a very short paved strip and my throttle and mixture cables had broken or stuck full open. You could always kill the engine with the fuel shut off valve but I have no idea how long that would take to kill the engine. I don't think I'd want to be rocketing it in a 1400' strip with no mixture to kill or throttle to pull back and only breaks to stop me.

Are we out of fuel or on fire? If not, why not fly to the longest runway that's within our range and pointed as close as possible into the wind? Then you could cut the engine off on short final (with lots of excess energy of course, no need to land on the threshold!) and float down the runway bleeding that energy off and touch down.

I would land gear up on purpose if ditching. That would help prevent you from flipping over during the landing.

As Ken stated, that may not be any better. I honestly don't know what I'd do for sure, but especially in higher seas I'd suspect that with the gear down you'd be in a more controllable situation. The gear would slow you down pretty quickly, so when the fuselage hits the water you're not going that fast. Definitely have to keep the nose way up though!

 

[Let'sgoflying!]

here is one time I would be sure to try to land with wheels up:

http://youtube.com/watch?v=BWzeFkGOUt8

 

[ScottM]

Another interesting one with asymmetrical landing gear on turf

Note he turned off and feathered the right engine prior to touch down. I am not so sure I would have done that. If for any reason he needed to do a go around his choice is no severely limited if not impossible.

 

[TMetzinger]

Nicely done! I had a bad moment on the first bounce, but the pilot recovered very well.

 

[poadeleted20]

Which gear? Partially extended or full up? What plane?

As with the other thread, the specific parameters change the answer, and without them, it's just too vague to give a supportable answer.

 

[TMetzinger]

Which gear? Partially extended or full up? What plane?

As with the other thread, the specific parameters change the answer, and without them, it's just too vague to give a supportable answer.

Ah, wait a second - you misread the question - you can pick your own airplane and own circumstances... what would make you decide to deliberately land an airplane with the gear up on a runway?

I'm looking for examples where it can be argued as the least risky alternative.

 

[AdamZ]

They also had both doors open. Did you notice how fast they got out of the aircraft. Impressive.

 

[Teller1900]

Asymmetric main gear extension. That's the only thing I can think of. If the nose is out, but no mains...well the tail is gonna hit no matter what, at least there's still some rubber for steering. If the mains and no nose gear is out...you'll save a lot of metal and possibly two engines (if so equipped) by leaving them down. With only one main down, though, I think controllability is going to be difficult, especially if you have tall gear or fast approach speeds.

 

[Everskyward]

Ah, wait a second - you misread the question - you can pick your own airplane and own circumstances... what would make you decide to deliberately land an airplane with the gear up on a runway?

I'm looking for examples where it can be argued as the least risky alternative.

If the nosegear in a Hawker comes down cocked as evidenced by the position of the tiller, the checklist procedure is to make a gear up landing. This is seen as better than the possibility of departing the side of the runway at a high rate of speed because you are unable to steer.

 

[Teller1900]

Note he turned off and feathered the right engine prior to touch down. I am not so sure I would have done that. If for any reason he needed to do a go around his choice is no severely limited if not impossible.

As Ron would say, I guess it depends upon the situation . Calm winds and you know you have priority for the field (which I'd say he did), might as well save the engine. Uncontrolled field or unpredictable winds/conditions...might want to keep the go around option.

 

[flyingcheesehead]

Nicely done! I had a bad moment on the first bounce, but the pilot recovered very well.

And watch the control surfaces - Fly the plane all the way through the crash! Very nicely done, with the exception of feathering a good engine (assuming again - It's not an Apache after all. )

 

[jesse]

On the retracts I've flown:

1.) If the nosewheel came down and the mains did not I would leave the nosewheel down and land.

2.) If the mains came down and the nosewheel did not I would retract all the gear and belly the plane in. The insurance company will pay for it. I doubt it would flip if the nose was up--but really--why risk it. I'm more nervous about a flip with two mains than no mains. No mains is pretty safe.

3.) If one main came down and the nose wheel came down I would retract all the gear and belly it in.

4.) If one main came down and the nose didn't come down I would retract all the gear and belly it in.

The thing is--I have no fear of landing completely gear up. It is a controlled balanced situation that really doesn't ever go wrong on a light airplane.

If I have to question the controllability of the airplane with a certain gear combination it's not worth it. Pull the gear up, declare an emergency, go to a towered field, land slow, fly the airplane till it stops, and let the insurance company figure it out. I will be running the engine until the concrete stops the prop.

Don't try to be superman. Just let the prop hit the concrete and you'll live. A gear failure is the last thing that'll kill you in GA.

 

[Everskyward]

2.) If the mains came down and the nosewheel did not I would retract all the gear and belly the plane in. The insurance company will pay for it. I doubt it would flip if the nose was up--but really--why risk it. I'm more nervous about a flip with two mains than no mains. No mains is pretty safe.

I was faced with this situation a number of years ago and elected to do the opposite. I landed with the mains down. This was in a C-320 which has a fairly long nosegear, and a ways for the nose to drop. It never really occurred to me to land with the mains retracted. What also didn't occur to me was that you have no steering after you slow down enough for the rudder to become ineffective. I also learned that people will ask questions about what you did or didn't do no matter what happens, and not just on the internet. This happened way before the internet days. Luckily the two entities that counted, my boss and the FAA, thought I did fine.

 

[jesse]

I was faced with this situation a number of years ago and elected to do the opposite. I landed with the mains down. This was in a C-320 which has a fairly long nosegear, and a ways for the nose to drop. It never really occurred to me to land with the mains retracted. What also didn't occur to me was that you have no steering after you slow down enough for the rudder to become ineffective. I also learned that people will ask questions about what you did or didn't do no matter what happens, and not just on the internet. This happened way before the internet days. Luckily the two entities that counted, my boss and the FAA, thought I did fine.

If what you did worked--it was the right thing to do. I can't stand it when people question someone that walked away.

 

[KennyFlys]

If what you did worked--it was the right thing to do. I can't stand it when people question someone that walked away.

Had I stayed close to aviation after my IMC incident years ago, I wonder how I might have been looked at. The reality is, it influenced how I teach. So, something positive came from it on top of my own learning experience.

 

[rubber314chicken]

On the retracts I've flown:

1.) If the nosewheel came down and the mains did not I would leave the nosewheel down and land.

2.) If the mains came down and the nosewheel did not I would retract all the gear and belly the plane in. The insurance company will pay for it. I doubt it would flip if the nose was up--but really--why risk it. I'm more nervous about a flip with two mains than no mains. No mains is pretty safe.

3.) If one main came down and the nose wheel came down I would retract all the gear and belly it in.

4.) If one main came down and the nose didn't come down I would retract all the gear and belly it in.

The thing is--I have no fear of landing completely gear up. It is a controlled balanced situation that really doesn't ever go wrong on a light airplane.

If I have to question the controllability of the airplane with a certain gear combination it's not worth it. Pull the gear up, declare an emergency, go to a towered field, land slow, fly the airplane till it stops, and let the insurance company figure it out. I will be running the engine until the concrete stops the prop.

Don't try to be superman. Just let the prop hit the concrete and you'll live. A gear failure is the last thing that'll kill you in GA.

I agree, however if it was a large jumbo jet I'd rather keep the main wheels down like in #2 to isolate the damage as much as possible. I doubt it would flip.

and I'd kill the engine on final as well to try and salvage the engine. as long as the runway is long enough though.

 

[Henning]

Water, wheat, beans, row crops, plowed fields. Anytime the addition of gear would increase my decellerational load beyond what I considered acceptable or create an assymetrical decelleration.

 

[jesse]

and I'd kill the engine on final as well to try and salvage the engine. as long as the runway is long enough though.

What is more important to you? Saving the engine or saving your skin? I'm not saying that you can't shut it down and live. I'm saying that shutting the engine down is the best way to make your gear failure turn into a fatal accident.

Statistics indicate very clearly that fatal gear up landings in light airplanes are almost always the result of the pilot shutting the engine down. The airplane is already going to get smashed up--don't make it more risky trying to save an engine that the insurance company will buy.

Your gear failed. You have an emergency. Don't add another emergency to the list. Just my opinion.

 

[rubber314chicken]

What is more important to you? Saving the engine or saving your skin? I'm not saying that you can't shut it down and live. I'm saying that shutting the engine down is the best way to make your gear failure turn into a fatal accident.

Statistics indicate very clearly that fatal gear up landings in light airplanes are almost always the result of the pilot shutting the engine down. The airplane is already going to get smashed up--don't make it more risky trying to save an engine that the insurance company will buy.

Your gear failed. You have an emergency. Don't add another emergency to the list. Just my opinion.

yea, but if You had 7,000 feet of runway, needed only 500 of that, and were on final, wouldn't you pull the mixture knob right before you flare? I would.

 

[jesse]

yea, but if You had 7,000 feet of runway, needed only 500 of that, and were on final, wouldn't you pull the mixture knob right before you flare? I would.

Nope. Whats the chance of the prop stopping sideways anyways? If it doesn't then you're going to need to sit there trying to bump it sideways. Its too big of a distraction.

 

[Tim]

Too many variables.................

 

[rubber314chicken]

Nope. Whats the chance of the prop stopping sideways anyways? If it doesn't then you're going to need to sit there trying to bump it sideways. Its too big of a distraction.

touche (there should be an accent on that e)