Colgan 3407 Down in Buffalo

[Stifler's Mom]

I was reading an airticle on CNN.com yesterday, and in the article it mentioned that the airspeed was at 100-110 kts just before the crash. Not sure if they meant during the impact, or just before the possible stall. When I went looking for the article again, it was gone.

That speed seemed very slow, and I wanted to verify what I had read. Anybody else see that?

 

[Andy Neill]

One issue I have not heard addressed yet is the probability of an accelerated stall. At some point in the event, 2 g's were experienced. That would have the effect of an increase of stall speed by 41%. A plane flown on approach at 1.3 Vso that then pulls 2g's will stall. If the plane was flying below 1.3 Vso (as several have implied) that would stall it with less of a g pull.

 

[LJ45]

One issue I have not heard addressed yet is the probability of an accelerated stall. At some point in the event, 2 g's were experienced. That would have the effect of an increase of stall speed by 41%. A plane flown on approach at 1.3 Vso that then pulls 2g's will stall. If the plane was flying below 1.3 Vso (as several have implied) that would stall it with less of a g pull.

They pitched up to 31 degrees quickly, either it stalled during that pitch up or pulled g's ??

 

[q100]

Its because you are training in a 121 Commerical environment. You're not doing full stalls on the commerical level like you did in the underpowered Piper or Cessna.
Its the first indication of stall, the shaker or buffet you are instructed to recover then.
Added power and either leveling your pitch or maybe lowering a bit should get you out of the impending stall easily.

So no, the 'airline method' is not a$$ backwards.

Thanks for reply - I actually am aware of all you are saying. 5000+ hours on Dash8 100s....

It's not bass ackwards in general, but it is bass ackwards from the way we learn stall recoveries from day one of student pilot training, which is first and foremost reduce the angle of attack by reducing pitch.

And my point was this - in trying to maintain pitch attitude against a pusher, a pilot could conceivably use enough force to over-ride the pusher, at which time 80# of backpressure would be transmitted to the elevator un-opposed, with a pretty rapid pitch up almost inevitable.

Also, have any of us driven an airliner, either for real or in the sim, into a stick shaker with the autopilot on? I can't remember doing so. I would imagine that having the a/p kick off as the stick shaker fires could lead to some interesting reactions!

As I said, I dunno what happened. I am trying to understand - 3407 hit pretty close to home with me. But I am far from convinced that the 121 way of doing stall recoveries is foolproof.

 

[Newf Dog]

Regarding taking a closer look at airline stall training:

I know that stall training did change at Comair after the Pinnacle accident for the simple reason that stall recognition and recovery techniques in the low altitude terminal environment (classic stall spin scenario) are different than stall recognition and recovery techniques in the high altitude environment.

Training and FSM were adjusted to reflect this disparity. Not saying it's relevant here necessarily. It's just that accidents usually do reveal areas where training needs to be adjusted. Unfortunately that is the "blood priority" with which we are all too familiar.

 

[livin'thesim]

I'm with q100. The problem is that smoothness is over-emphasized in many 121 programs' stall recovery training.

The emphasis on altitude control by many check airmen causes, in my opinion, too much concern about the wrong thing.

The typical 121 stall training works well for crews that find themselves a little slow, and just bumping into the shaker a bit.

It's not aggressive enough for a full-stall situation.

In reality, what passes for stall training in the transport category world would be better termed: Recovery from unintentional slow flight
training.

The nonsensical emphasis on altitude control in simulators instead of pitch control is not helping.

Pitch control is much easier to train, and it leads to more consistent results in training. Also, it gets the eyes where they need to be, which is on the aircraft's pitch attitude.

I've done my share of time as a sim instructor, and I am not at all convinced that typical 121 "stall training" should even have the word 'stall' in it.

 

[WSurf]

Thanks for reply - I actually am aware of all you are saying. 5000+ hours on Dash8 100s....

It's not bass ackwards in general, but it is bass ackwards from the way we learn stall recoveries from day one of student pilot training, which is first and foremost reduce the angle of attack by reducing pitch.

And my point was this - in trying to maintain pitch attitude against a pusher, a pilot could conceivably use enough force to over-ride the pusher, at which time 80# of backpressure would be transmitted to the elevator un-opposed, with a pretty rapid pitch up almost inevitable.

Also, have any of us driven an airliner, either for real or in the sim, into a stick shaker with the autopilot on? I can't remember doing so. I would imagine that having the a/p kick off as the stick shaker fires could lead to some interesting reactions!

As I said, I dunno what happened. I am trying to understand - 3407 hit pretty close to home with me. But I am far from convinced that the 121 way of doing stall recoveries is foolproof.

True, and I understand where your coming from. And with the Stick PUSHER coming on, I would agree with you that your only recourse at that time is to lower the pitch while adding power. I mean the plane is yelling at you "hey dummy lower the pitch and increase airspeed I am about to stop flying."
But like I said, I think maybe the crew was really worried about the ice and it became their main focus rather then the airspeed of the plane. 2 pilots and neither one watchin the planes airspeed get to 134kts with no gear selected down. I believe they were both worried about ice on the windshield and wings.



Back to the Stick Pusher: We usually don't train that point of pusher or shaker, mainly because you should never, ever, ever allow that plane to even get close to that point.

You are right in the fact that Stick Shaker and Stick Pusher recovers would be different.

 

[livin'thesim]

You're right, and you may have hit on the real tragedy here. The distraction from the ice may have been a bigger factor than the aerodynamic effect.

 

[ackattacker]

I can say that in my 121 training I never did any maneuver that resulted in a stick pusher. I have no idea what it feels like, how far the nose drops, etc. Stall training goes to the shaker and then recovery... and with the autopilot off. I'd expect this accident may (and should) result in a change in training.

 

[Flyin2low]

Also, have any of us driven an airliner, either for real or in the sim, into a stick shaker with the autopilot on? I can't remember doing so. I would imagine that having the a/p kick off as the stick shaker fires could lead to some interesting reactions!

Actually my airline does.

But I think you mean 'stick pusher'. And a fed had the IP do that to us on our type ride in the CRJ. While doing an approach briefing on downwind, stick pusher activates and A/P disconnects. The funniest thing was that after releasing the A/P disconnect, it did it again until we figured out to turn off one of the stick pusher switches.

 

[imadumbpilot]

Also, have any of us driven an airliner, either for real or in the sim, into a stick shaker with the autopilot on? I can't remember doing so. I would imagine that having the a/p kick off as the stick shaker fires could lead to some interesting reactions!

This is a maneuver that they used to train at ACA, the reason is because they had an accident in 1994 on a J41 in CMH, where the crew stalled the airplane on approach with the autopilot on. It was quite a different stall from what you normally saw. It has been a long time, but I think that the autopilot warning was inhibited because the stall warning took precedence. There was some question about weather or not that crew realized the autopilot had disconnected. Anyway, it is an interesting question and good to train that way.

 

[surplus1]

Maybe there's just something wrong with me.

I understand the concept of approach to stall recovery with minimum loss of altitude. Shaker is an approach to a stall.

I do not understand a concept of zero loss of altitude at any cost, and difinetely do not believe that is possible in the real world of line flying - especially in IMC. Maybe you can do that neat trick in simulators - but it's still a trick.

Nobody intentionaly activates a shaker in the real world. Simulators are wonderful tools but they are not real airplanes. You don't ever practice stalls in a real airliner full of people.

I just can't imagine a training program that would tell you to put the yoke in your stomach at the sound of the shacker because you might lose 100 ft of altitude, or even 200 ft.

Also, I do not understand how a pilot looking at an ADI that shows the nose rising rapidly would continue to apply back pressure in hopes that would change. Maybe someone studying for an instrument ticket - but an ATP with several thousand hours and assisted by a compentent F/O?

Putting the nose at the level-flight deck angle and powering out of the approach to stall makes sense to me.

Sucking the yoke into my stomach in an effort to avoid losing some altitude, just dosen't make sense in my head.

I've been driving airplanes since I was 20 years old. 20 years of that was in airiplanes much larger than a Q-400 - some with popellers and some without, followed by another 12 years in airplanes of similar size. I don't remember anyone ever telling me to do that and if they had I'm real sure of what I would have told them to do with that idea.

If that is what were teaching pilots to do we'd better revise that program in one hell of a hurry.

Training needs to fit the real world. If you near stall at 200 ft AGL in anything but a toy airplane the ground will come up and smite you 99/100 no matter what you do. 121 has nothing to do with that.

If you lose 100 ft anywhere above 500 ft, chances are it wont - again regardless of 121.

I just have a hard time understanding that people would intentionally teach this Captain how to kill himself and his passengers.

Of course none of us has heard the CVR - hopefully it will provide the AI's a better understanding of what took place - if they said anyting relevant after the shaker went off.

At this point I'm a lot more worried about what happened after the shaker than how they got there in the first instance.

Apologies for the rant - it just doesn't compute.

 

[172driver]

Surplus,

Spot on as usual, but I'm afraid that is how it's trained. It's the FAA, not the airlines. We do it the same in our 135 training. I've thought it was stupid and dangerous since the first time I did it. In a clean CRJ, they want you to hold the pitch at 12-15 degrees as I remember, don't let it drop at all. Very standardized and neato, but dangerous as hell in the real world. Even in the sim, I have seen secondary stalls and pushers activated due to this wonderful technique.

 

[Raskal]

Here is an unfortunately fair and well-written article:

http://www.nytimes.com/2009/02/19/nyregion/19crash.html?_r=1

My guess is because there isn't a tv journalist involved there isn't the usual amount of sensationalism and bullsh!t.

 

[climbhappy]

i know on the boeing, the trick is to watch the angel wings come down and you maintain pitch to about 5 degrees and ram it up.

like you said, sims tricks...

 

[Donsa320]

I think most of you folks are on to it now. Also, consider that the spread between shaker and pusher could have been very narrow with a little ice contamination on the airplane.
Many really good comments.

 

[belchfire]

In a transport with all engines operating there is tremendous excess thrust at landing weights. There's no reason to lower the nose because of that excess power. Start thrashing around with the yoke and you're going to induce pitch osolations. Radar power and roll wings level and hold what you have in pitch...if it is a normal flight attitude.

Unless it is an upset of course and that's a different situation

 

[surplus1]

In a transport with all engines operating there is tremendous excess thrust at landing weights. There's no reason to lower the nose because of that excess power. Start thrashing around with the yoke and you're going to induce pitch osolations. Radar power and roll wings level and hold what you have in pitch...if it is a normal flight attitude.

Unless it is an upset of course and that's a different situation

Belchfire, I agree with you. In a normal level flight attitude, at any altitude below 10K (and that's very conservative), whether turning or not, add max power, hold the pitch you have and roll wings level. You'll power right out of the shaker or buffett. If you yank on the yoke you virtually guarantee pusher activation and things are likely to go TU in a big hurry.

If you upset at low altitudes its guaranteed the ground will come up and smite you.

If you do it at higher altitudes it is highly probable that you will cause structural damage or simply tear the airplane apart in the effort to recover.

If its a jet with rear engine placement (and you do recover from the upset), the probability of a flame-out on 1 or both is very high. Better hope you're not over the Andies, the Alps, the Caucauses, the Rockies or those giants in Asia. Many would require drift-down before you can even attempt to re-light.

Unless you're very close to the ground, and I mean two hundred feet or less, it doesn't matter one iota if you lose 100 or 200 feet in the process. The objective is to keep the wing flying and avoid stalling it.

There's one 4-eng proppeller transport that I once flew (Not a C-130), which at low landing weight had so much excess power that you could literraly nurse a go-around with 3 inop. Not something that was recommended or probable but something that was possible under ideal conditions. With 2 out on the same side it was not extremely difficult.

There was another (twin), with so much power that the 1st immediate action after engine failure on TO was to reduce power on the good engine - to relieve/reduce too high rudder pressure. I always felt (personally) that the fin/rudder was too small on that type. They modified the tail but the aircraft wasn't really designed for those engines.

According to the manufacturer, the engines on the Q-400 ea produce 5071 shp. That's a whole lot of power for a 55,000 lb landing weight. I would imagine it would have no trouble at all powering out of a shaker on final approach.

This is a very sad story and if what it now looks like proves to be true, the training for this type will require some major revisions.

If this captain pulled hard on the yoke when the shaker went off - it probably follows he was trained to do just that.

If true, I don't see it as pilot error - although I think they will call it that. I see it as being trained how to induce an upset and lose your airplane.

 

[JAKEFAC]

I think the technique taught now for stall recovery - with a flight director - is at the first indication of a shaker is to hold what you have with regards to pitch attitude - this will indicate level flight at the time of approach to stall and to power out of it using all available thrust. Depending on the thrust vector of the engines and the type of airplane, this might require slight back pressure (or slight push over) to maintain desired pitch - but nothing as aggressive as has been suggested might have occurred. The elevator trim as positionned by the autopilot trying to maintain a set altitude with reduced power would also come into play and would have to be countered with - for a rapid increase in thrust.

 

[Oakum_Boy]

Yeah, diving the nose to negative 10-20 degrees isn't appropriate. You're gonna be in a heck of a descent at that point. But pulling against a stick pusher just seems so counter intuitive, but being that close to the ground at night, in IMC...