thoughts on stalls
#51
ptarmigan,
Q-alpha video:
A circle of lights changing color and a mechanical voice calling attention to an airspeed problem.
What's the difference between that and either (or both) PF and PM noting the airspeed problem on their airspeed indicator while the PM constantly repeats "airspeed" until a correction?
Same question for the stall recognition and entry into stick-shaker. How is the "errant mental model" going to be prevented any more effectively? Why is a voice announcing "stall" and a red circle of lights is any more effective than a stick-shaker, airspeed indicator in the red-zipper and pitch at the PLI.
Pilots manage to ignore audible gear warning systems now and then. I don't see why this system is any different. It seems to me that it has the potential to put the PF or perhaps the whole crew into audio overload as they try to communicate effectively to resolve the situation with that thing blaring constantly in their ears.
Q-alpha video:
A circle of lights changing color and a mechanical voice calling attention to an airspeed problem.
What's the difference between that and either (or both) PF and PM noting the airspeed problem on their airspeed indicator while the PM constantly repeats "airspeed" until a correction?
Same question for the stall recognition and entry into stick-shaker. How is the "errant mental model" going to be prevented any more effectively? Why is a voice announcing "stall" and a red circle of lights is any more effective than a stick-shaker, airspeed indicator in the red-zipper and pitch at the PLI.
Pilots manage to ignore audible gear warning systems now and then. I don't see why this system is any different. It seems to me that it has the potential to put the PF or perhaps the whole crew into audio overload as they try to communicate effectively to resolve the situation with that thing blaring constantly in their ears.
Essentially the q-alpha would alert quite a bit earlier. As I recall from his SETP presentation, the system would alert significantly higher than a system based solely on alpha, I think the numbers were something like 30% over Vs as opposed to around 9% for current systems.
#52
Q-alpha warning starts quite a bit earlier as it is looking at both q and alpha, independently. The actual margin prior to stall for just an alpha based system is quite low.
Essentially the q-alpha would alert quite a bit earlier. As I recall from his SETP presentation, the system would alert significantly higher than a system based solely on alpha, I think the numbers were something like 30% over Vs as opposed to around 9% for current systems.
Essentially the q-alpha would alert quite a bit earlier. As I recall from his SETP presentation, the system would alert significantly higher than a system based solely on alpha, I think the numbers were something like 30% over Vs as opposed to around 9% for current systems.
#53
#54
Actually, looks like he has the SETP presentation on his website:
https://drive.google.com/file/d/1wGc...9BffCOVrU/view
https://drive.google.com/file/d/1wGc...9BffCOVrU/view
#55
Disinterested Third Party
Joined APC: Jun 2012
Posts: 5,996
The assumption is that if the aircraft had been barking airspeed constantly, the Colgan crew would have not taken the airplane to the shaker, and beyond. The Captain pushed the power to the 70 degree point, the pusher then broke the stall, but the FO put the flaps to 0. Clearly, the startle factor with confusion, was an issue in this accident.
For reasons of mitigating inadvertent activation, the stick shaker margin has been significantly reduced from its original design. In fact, in the patent, the auto-pilot was to remain on, and do the recovery procedure, not the pilot.
For reasons of mitigating inadvertent activation, the stick shaker margin has been significantly reduced from its original design. In fact, in the patent, the auto-pilot was to remain on, and do the recovery procedure, not the pilot.
#56
The stick shaker was continuous, and indeed in the case of the Colgan mishap, activated some 20 knots sooner than it would normally activate, due to incorrect crew configuration of the stall warning system for icing conditions. Neither shaker, nor airspeed indication, nor stall annunciation, nor airframe buffet, nor pusher activation served to alert the pilot to the need to recover from a stall...or push the power up beyond partial, for that matter. Go figure.
1. Stick pusher was not taught;
2. Higher stall speed warning. Would that lead to someone thinking that the stall warning was false? We have seen that in multiple accidents.
3. Combination of stick pusher with the above meet several of the criteria in that video for a tail stall.
#57
Apparently we'll never believe we're stalled unless we get told repeatedly ahead of time.
#58
Read the article from B/CA, they’ll sell to corporate operators because the owners want anything, and I mean anything, that boosts their ego or might preserve their life. Airlines won’t spend the money because they pilots to be pilots and be aware of airspeed. I’m glad Rosey liked it.
The simple rule: Watch thy airspeed, lest the Earth rise up and smite thee. Worked well for 50 years.
GF
The simple rule: Watch thy airspeed, lest the Earth rise up and smite thee. Worked well for 50 years.
GF
#59
Disinterested Third Party
Joined APC: Jun 2012
Posts: 5,996
That explains a lot.
Johnathan, you're stalling.
No, I'm not.
Everyone says that.
I know, but I'm not really stalling. I feel fine.
No, Johnathan. The airplane is stalling.
No, it's not.
You've exceeded your critical angle of attack.
No, it was just an argument. I'll buy her flowers later.
Johnathan, you're in denial.
It can't be. I'm thirty thousand feet over it. There it is, right there.
Johnathan, your nose is too high.
Have you been talking to my wife?
You need to take action soon, Johnathan. Lower your nose.
Ok, look, we've agreed to seek counseling, but I don't see how it's any of your business.
Johnathan, you're contending with confirmation bias. You're seeing what you want to see.
Well, we both are. It's an open marriage.
You think you're not stalling, but you are.
I might be delaying a little, that's all. I'm undecided.
Add some power, Johnathan.
So you're saying I should take back my masculinity?
Johnathan, you're not getting it. Look at your airspeed.
Ah, yes. There it is. Not even close to being overspeed. In fact, look how low it is. Nice and safe. Nothing to break here.
The airplane is buffeting, Johnathan.
Well, I do feel hungry. Good call.
Fly the airplane, Johnathan. Do your job.
No, need, thanks. I have this spiffy autopilot right here. It will tell me if something's wrong.
I'm telling you, Johnathan. Something is wrong. Something is very, very wrong.
Who did you say you are?
I'm your training, Johnathan.
Oh, that again. I finished all that, thanks. I became an airline pilot so I don't have to do that any more. A computer course, a quick spin in a sim, like a big video game. A lot like this, really.
You won't get to train again, Johnathan, because if you don't recover, there won't be any more agains.
That's a bit of a low blow. I'm recovering. My name is Johnathan, and I'm recovering. There's no such thing as recovered, you know.
Johnathan, push up the power, lower the nose, level your wings, and climb. We're going down.
Look, I know you're trying to help, but the airplane's just not doing what I want. I push this control, the airplane does that. I pull back, it doesn't go up. I roll left, the airplane starts to go right.
You're fully stalled, Johnathan.
No, I just think it's broken. I'm going to ask for another one.
It's a swept wing airplane, Johnathan.
It is clean, isn't it? And shiny.
It won't be for long, Johnathan.
I now, but they employee people to fix that.
You're employed to fix that, Johnathan. Do it. Do it now.
This flopping around is making me tired. I'm going to rest. You take care of it. In the meantime, just let me know if anything's wrong, ok?
Goodby, John.
Bye.
#60
Line Holder
Joined APC: Oct 2010
Position: B757
Posts: 84
Neither shaker, nor airspeed indication, nor stall annunciation, nor airframe buffet, nor pusher activation served to alert the pilot to the need to recover from a stall...[/QUOTE]
..I´m with JB on this one..We still got people flying out there, who should not be in the cockpit at all..For these ´´pilots´´, it doesn´t matter how good the safety systems are, or how good their training, they will always find a way to f--- up (excuse my language) something..Usually these same people have a long history of incidents / violations also, yet they still continue to get access to the cockpit..The big question in my mind is, what can be done to keep them out ??
Fly Safe,
B757
..I´m with JB on this one..We still got people flying out there, who should not be in the cockpit at all..For these ´´pilots´´, it doesn´t matter how good the safety systems are, or how good their training, they will always find a way to f--- up (excuse my language) something..Usually these same people have a long history of incidents / violations also, yet they still continue to get access to the cockpit..The big question in my mind is, what can be done to keep them out ??
Fly Safe,
B757
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