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.