Pilot-Induced Oscillation

It looked like it went off the runway edge. That was perferable paying for the fuel to go around?

There seems to be a mentality among some that says, "I can save it!"
 
Why didn't he add power? and either go around or stop the nose down attitude?
I have done that exact thing twice with a cardinal. Ask Nick. screwy high wings. It will get your heart going, but it seems like second nature to add power after the first bounce. Wonder what the story is.
 
Wow ..seriously...just WOW.....
did the pilot bounce and then just slam the yoke forward and hold it against the panel or something...at least pull up to level it or something...
a reaction to pull back should be second nature to ANY pilot...he seemed to just beelive that he could just keep jamming the nose into the pavement and he would eventually land smoothe..

seriously..this pilot should be executed before he kills alot of people..
its obvious this guy should still be in flight school flying a c150...
 
SupraPilot said:
Wow ..seriously...just WOW.....
did the pilot bounce and then just slam the yoke forward and hold it against the panel or something...at least pull up to level it or something...
a reaction to pull back should be second nature to ANY pilot...he seemed to just beelive that he could just keep jamming the nose into the pavement and he would eventually land smoothe..
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I don't think he was jamming the nose into the pavement. Once you start to bounce like this it'll keep on doing it. I don't know a thing about flying something like that so all I've got to say is--cool video.

SupraPilot said:
seriously..this pilot should be executed before he kills alot of people..
its obvious this guy should still be in flight school flying a c150...
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I think that may be a little bit too far.
 
Michael said:
Why didn't he add power? and either go around or stop the nose down attitude?
I have done that exact thing twice with a cardinal. Ask Nick. screwy high wings. It will get your heart going, but it seems like second nature to add power after the first bounce. Wonder what the story is.
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One of the comments on the video suggests it was a student military pilot. His reply is in response to someone who suggested those Russian pilots needed to lay off the vodka:

ppl don't be so stupid !!! it's in military school it was his second land and it's not funny. after first impact his headphones left from head and he did not hear as the instructor from the ground spoke him what to do... Overloads reached up to 7G, all have received serious traumas. At the plane the forward rack of the chassis broken and the big destructions in a cabin. Sorry for my eng, but i can't hear about it somthing stupid like "pilots shouldn't drink so much vodka" :mad:
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Troy Whistman said:
One of the comments on the video suggests it was a student military pilot. His reply is in response to someone who suggested those Russian pilots needed to lay off the vodka:
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Thanks Troy. Sounds like an explanation to me.
 
It looks like he blew the tires, and that's what finally stopped him....am I correct there?
 
Too fast, didn't flare, flew it onto the runway then tried to dive it in several times instead of letting the speed bleed off.

I hope there weren't pax on that...
 
Couldn't this have been an elevator failure landing? It looks like even in the biggest bounces, the elevator does not change positions. The nose goes up, airspeed decreases, then the nose goes down. Not even the slightest attempt to correct. I think anyone who has ever flown anything bigger than a 152 could have done better.

I really think there was some type of control failure involved. I could be wrong but I really think anyone flying this size aircraft would not be capable of such a landing without some other factors involved.
 
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fishnfly said:
Couldn't this have been an elevator failure landing? It looks like even in the biggest bounces, the elevator does not change positions. The nose goes up, airspeed decreases, then the nose goes down. Not even the slightest attempt to correct. I think anyone who has ever flown anything bigger than a 152 could have done better.
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That is the beauty of it. You get an airplane bouncing and it'll do this until it crashes. Apply power--get the hell out of there. This is exactly how MANY Cessna 182s are trashed.

fishnfly said:
I really think there was some type of control failure involved. I could be wrong but I really think anyone flying this size aircraft would not be capable of such a landing without some other factors involved.
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The beauty of the military is you step up fast. I'm sure everyone has accidents and I don't know much about the Russian's air force training. A control failure is very unlikely. I'd put my money on it being a student pilot that froze up.

The Stearman is a perfect example of a trainer that was built with the intentions of having the crappy pilots crash. Many were busted up--many pilots were killed. But the crappy pilots were filtered out early and airplanes and pilots were cheap. If they get killed who cares there are hundreds of thousands of other potential pilots. If the airplane gets trashed--who cares..build another one. It's funny how much the value of a human life decreases in times of desperation.

I wouldn't be surprised if many of the pilots that couldn't handle the stearman were stuck in an Army glider.
 
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fishnfly said:
Couldn't this have been an elevator failure landing? It looks like even in the biggest bounces, the elevator does not change positions. The nose goes up, airspeed decreases, then the nose goes down. Not even the slightest attempt to correct. I think anyone who has ever flown anything bigger than a 152 could have done better.

I really think there was some type of control failure involved. I could be wrong but I really think anyone flying this size aircraft would not be capable of such a landing without some other factors involved.
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But wouldnt adding power decrease the sink rate and possibly raise the nose?
 
Michael said:
But wouldnt adding power decrease the sink rate and possibly raise the nose?
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Yes it would, and like I said, I could be wrong about what I said. Others have pointed out some excellent possibilities like it just could be a rookie pilot. I just thought I'd throw the elevator failure possibility out there.
 
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You *CAN* save the porpoise without adding power. Well, maybe you can't, but I can.
 
EdFred said:
You *CAN* save the porpoise without adding power. Well, maybe you can't, but I can.
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Indeed, it can be done (and has by me)....

I once porpoised the hell out of a 172 when I was a student on my first attempt at my first cross country solo. CFI never covered what to do when you porpoise.

So what I did was level off, no power added, just during one of the bumps, levelled off, and sunk to the ground rather rapidly. Basically a 4 foot flare.

But from that, I can say that you could also bring it down more gradually as well without power.
 
Landed well above Vref. Too much energy still available. Touchdown is almost flat....
 
Michael said:
But wouldnt adding power decrease the sink rate and possibly raise the nose?
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Yep, but a turbine doesn't spool up like a recip. You don't get instantaneous power, but he didn't really need any, just a bit more skill on the stick, but he probably didn't have the experience considering it a training flight.
 
jesse said:
That is the beauty of it. You get an airplane bouncing and it'll do this until it crashes. Apply power--get the hell out of there. This is exactly how MANY Cessna 182s are trashed.
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its not the airplane that does this..its the pilot...the airplane will keep bouncing as long as the pilot isn't doing anything to control the problem..

this is what i meant..you can clearly see the pilot just kept trying to force it down...unless this was a control failure, then this pilot needs a little more pattern work :dunno: ..thats why its called PILOT induced oscillation...not AIRCRAFT induced oscillation...
 
SupraPilot said:
its not the airplane that does this..its the pilot...the airplane will keep bouncing as long as the pilot isn't doing anything to control the problem..
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With something this large I suspect after the first bounce like that the situation would get very difficult to control. Obviously he messed up. Obviously he caused it. But this kind of stuff can happen to anyone. The second you think it can't happen to you is the second you get in trouble.

SupraPilot said:
this is what i meant..you can clearly see the pilot just kept trying to force it down...unless this was a control failure, then this pilot needs a little more pattern work :dunno: ..thats why its called PILOT induced oscillation...not AIRCRAFT induced oscillation...
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I doubt he was trying to force it down as much as he wasn't doing anything. The control inputs it can take to recover from a situation like this are not exactly easy. As soon as it bounces back up you most likely do not have enough airspeed to fly away. In a jet it'll take some time to get power. Quite often when it bounces back up you'd need to shove the stick forward to reduce wing loading and try to get it under control. Before it hits the ground you'd need to pull back slightly and try to control the sink rate. Do it too hard either way and the situation gets worse. Keep pulling back and you may keep on bouncing.

I had something similar to that happen during my tailwheel training. Bounced and the plane jumped up and started to come down hard again. I slammed the stick forward followed by pulling back again slowly to get it under control. It's probably smarter to just go around. That's easy to do in a piston and sometimes not so easy to do in certain jets or turbines.
 
On a transport category aircraft there is only one airspeed for landing, it is called Vref, and it is an angle of attack specified for weight, called, Vref.

If you land fast, this happens. If you land slow, you hit the tail. This is unlike the behavior of say, a P28A (which I had the privelage of again flying today) :).
 
Pitch the nose up, hold it up, and add power -- that's pretty much the solution in any airplane. If there's enough runway, you can try to reestablish things and make a landing, but once you feel the nosewheel hit with the mains off the ground, a go-around is almost always the best solution. It's pretty clear the L-410 pilot didn't do any of this.
 
Ron Levy said:
Pitch the nose up, hold it up, and add power -- that's pretty much the solution in any airplane.
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I doubt every situation is that simple. Lots of airplanes and lotsa funny things you can make them do.

I'm not so sure I would suggest you hold any airplane up if it doesn't want to be up anymore.

A pilot would really bust an airplane up in the wrong situation if they tried to hold it up and apply full power. Hot day, flaps, at gross airplane, high angle of attack, ground effect, and you're suggestion of holding it up and adding power will result in the nose coming back down hard.

There isn't a hard fast rule for anything in flying and it's hard to judge every situation based on a NTSB report or video. Listen to what the airplane is telling you as it occurs and most likely if you don't freeze up you'll do the right thing. I'm not suggesting you wouldn't Ron, I'm just saying what you wrote above isn't always going to save you. People need to be trained to react to the situation as it unfolds--not use some script for reacting.

There are two rules that you must always obey: Never force an airplane into the sky, and never force an airplane into the ground. If you do either one of those physics will win every time. I'm sure we both agree on that.
 
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Greg Bockelman said:
For a PIO, Jesse, Ron is right.
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There is no hard and fast rule for recovering. A PIO does not have to be during the landing phase. It's simply the pilot over correcting back and forth making the problem worse. Sometimes it's easier to just give up and hold the stick back and wait it out. Sometimes it's better to slam power and get the hell out of there. Sometimes it's better to fix it by just not over correcting.

We're going to have to agree to disagree on this one. I'm saying applying full power and forcing/holding an airplane nose up might just own you. It will not work in every situation.

If I am landing in a C150 at gross on a 100 degree day and I mess up I could get it to bounce off the nose. It would bounce back up a few feet and want to come back down. The best thing would be to try to reduce the sink rate with power and the controls. If I apply full power and hold the nose up trying to climb out with full flaps I promise you the airplane will climb a little and then stall coming down HARD on that nose. A C150 with full flaps, at gross, on a hot day, will NOT climb out without retracting flaps. Retracting flaps at this point in the game will also slam you into the runway.

Pilot induced oscillations have led to accidents with some of the most experienced test pilots on the controls. If this were such a simple problem it wouldn't be such a big deal during test and design.

PIO is considered throughout design and test of airplanes. Becoming a much larger problem on military and commercial planes.

http://www.amazon.com/Aviation-Safety-Pilot-Control-Understanding/dp/0309056888

Technical, not real applicable to our small ga airplanes, but still good.
 
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jesse said:
There is no hard and fast rule for recovering.
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I'd be interested to hear what airplane would have a different recovery technique for this situation. Even if you can't go around with full flaps, getting the nose up so the mains touch down first next time and the nose stays up after touchdown, and application of power to cushion the impact, is still the best solution once that crow-hopping starts.
A PIO does not have to be during the landing phase.
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Change the question, and you change the answer, but this was a discussion on a PIO on landing involving a nosewheel-first touchdown (about the second or third impact, in the video).
 
Ron Levy said:
I'd be interested to hear what airplane would have a different recovery technique for this situation.
.
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See the above. The first one I can think of is the C150.

I would also think some turbine airplanes would not develop enough power to climb out for a short time. That short time if you are hauling back and holding the nose up you'll be in trouble. You keep holding the nose up, the angle of attack keeps increasing every moment, and it takes quite some time to develop power to climb out. Lots'a piston pilots killed in early jets because of that very problem.
 
jesse said:
See the above. The first one I can think of is the C150.
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Having given over 500 hours of instruction in C-150/152 aircraft, and been through these more times than I have fingers and toes, I can tell you for absolute sure that holding the nose up and powering up is the way to handle the situation once you get that nose-then-mains bounce.
I would also think some turbine airplanes would not develop enough power to climb out for a short time. That short time if you are hauling back and holding the nose up you'll be in trouble. Lotsa' piston pilots killed in early jets because of that.
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Nobody said you have to climb out, but you do have to get the nose up and power on the jet to prevent collapsing the gear on the next crunch. There is really no other solution in any jet I've ever flown.
 
Ron Levy said:
Having given over 500 hours of instruction in C-150/152 aircraft, and been through these more times than I have fingers and toes, I can tell you for absolute sure that holding the nose up and powering up is the way to handle the situation once you get that nose-then-mains bounce.
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Well that's good. We're on the same page. I'm not saying that you shouldn't go around. Nor am I saying that you shouldn't keep the nose up if you can.

Really all I'm saying is that the way you wrote it will make some people think that they should jerk the nose up and try to keep it at some certain attitude no matter what. When you hold it up, airspeed will bleed off, and the angle of attack will increase at whatever attitude you select. If that angle of attack gets too high before you touch the runway again you'll be coming down harder then you wanted nose first. The problem with the lack of horse power is the angle of attack will increase faster than power can restore it. Hopefully you meet the runway before this happens or you decrease the angle of attack as needed.

The very act of the bounce on the runway might point the airplane at a higher nose attitude then you'd want. Too high and you'll stall before you touch the runway again. You want the nose up, yes, but you don't want to have it stall before you hit the runway again. This could mean that you would push at first to decrease the angle so that you could pull before you hit the runway. Of course if you do this wrong you'll just make the PIO worse.

There are many NTSB reports which make it very clear that a C150 at gross on a hot day with full flaps will not climb out of an airport. This makes it clear that with full flaps above ground effect your angle of attack will increase with any attitude that would produce a climb even with full power. So if you bounce too high you just might stall with any attitude above the horizon. I wouldn't think you'd bounce this hard but people do manage to do that kind of ****.

If only our eyes could see angle of attack. If it could you'd simply tell pilots to recover by pulling and keeping the angle somewhere near the critical angle but short of it until you touch again.

Ron, I know you are very capable of recovering from this. I just also know how some pilots have no understanding of angle of attack and will read words like "hold it up" as hold the nose way above the horizon and apply power.

Damn complicated airplanes anyways.
 
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jesse said:
Well that's good. We're on the same page. I'm not saying that you shouldn't go around. Nor am I saying that you shouldn't keep the nose up if you can.

Really all I'm saying is that the way you wrote it will make some people think that they should jerk the nose up and try to keep it at some certain attitude no matter what. When you hold it up, airspeed will bleed off, and the angle of attack will increase at whatever attitude you select. If that angle of attack gets too high before you touch the runway again you'll be coming down harder then you wanted nose first. The problem with the lack of horse power is the angle of attack will increase faster than power can restore it. Hopefully you meet the runway before this happens or you decrease the angle of attack as needed.

The very act of the bounce on the runway might point the airplane at a higher nose attitude then you'd want. Too high and you'll stall before you touch the runway again. You want the nose up, yes, but you don't want to have it stall before you hit the runway again. This could mean that you would push at first to decrease the angle so that you could pull before you hit the runway. Of course if you do this wrong you'll just make the PIO worse.

There are many NTSB reports which make it very clear that a C150 at gross on a hot day with full flaps will not climb out of an airport. This makes it clear that with full flaps above ground effect your angle of attack will increase with any attitude that would produce a climb even with full power. So if you bounce too high you just might stall with any attitude above the horizon. I wouldn't think you'd bounce this hard but people do manage to do that kind of ****.

If only our eyes could see angle of attack. If it could you'd simply tell pilots to recover by pulling and keeping the angle somewhere near the critical angle but short of it until you touch again.

Ron, I know you are very capable of recovering from this. I just also know how some pilots have no understanding of angle of attack and will read words like "hold it up" as hold the nose way above the horizon and apply power.

Damn complicated airplanes anyways.
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You're really not yanking back on the stick. You're freezing the stick slightly aft of neutral. This stops the PIO.
 
Patch said:
You're really not yanking back on the stick. You're freezing the stick slightly aft of neutral. This stops the PIO.
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You're doing what it takes to recover. What it might take depends on so many variables you can't say it'll always be one thing. That is what I was pointing out.
 
jesse said:
You're doing what it takes to recover. What it might take depends on so many variables you can't say it'll always be one thing. That is what I was pointing out.
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No. It's procedurally correct to freeze the stick slightly aft of neutral if in a PIO in the flare. The variable is whether to go to max power and execute a go around or continue the landing.
 
Patch said:
No. It's procedurally correct to freeze the stick slightly aft of neutral if in a PIO in the flare. The variable is whether to go to max power and execute a go around or continue the landing.
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If the PIO is hard enough--slightly aft isn't going to be enough. A go around is not always an option and continuing the landing isn't always an option. Recovering from this kind of stuff is a "seat of the pants" decision.
 
jesse said:
If the PIO is hard enough--slightly aft isn't going to be enough. A go around is not always an option and continuing the landing isn't always an option. Recovering from this kind of stuff is a "seat of the pants" decision.
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You do know what a PIO is, right?
 
Patch said:
You do know what a PIO is, right?
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Yes I do. I'm saying that recovery is completely dependent on the situation. Very few things are constant in this world.

BTW: I'm getting a kick out of how we are both talking between two different threads. By the time I respond to this one--you probably have already responded on the other one.
 
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