Qantas A330 Takes a Dive

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Rockie
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Re: Qantas A330 Takes a Dive

Post by Rockie »

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ALPHA FLOOR has nothing to do with the rudder. The aircraft will maintain an angle of attack without further pilot input down to the top of the amber and black stripe on the speed tape, which is called ALPHA PROT. Between ALPHA PROT and ALPHA MAX (top of the red stripe) is ALPHA FLOOR which is an autothrust function that automatically applies TOGA thrust, but has no effect on the pitch or the rudder. Within the amber and black band it requires increasing back pressure to maintain or increase angle of attack further up until the top of the red band. The top of the red band is the highest angle of attack the aircraft will achieve in normal law even with full back stick. In alternate or direct law the angle of attack protection is lost and it is possible to stall the aircraft.

I'm not sure what you mean with your question about the rudder. But in a transport category jet there is little if any rudder required even in direct law, and the same applies to conventional Boeing products with the yaw damper inoperative. The airplane just likes to fly straight.

iflyforpie

The accident you're referring to was a test flight in Toulouse with a bunch of engineers in the back. The profile called for an early altitude capture immediately after takeoff coincidental with failing an engine and I think a hydraulic system, but I'm not sure about that part. When any automatic airplane, doesn't matter who makes it, levels off it calculates a geometric arc from the point it enters the mode culminating in level flight at the desired altitude. The higher the rate of climb the earlier the aircraft enters the mode and the more elongated the arc.

The problem arises if you lose an engine at that point, because even though you have lost half your thrust the aircraft is still going to maintain that arc that it calculated when it had two engines. This inevitably leads to an airspeed loss. In the case in Toulouse I think there were some other factors complicating things as well, and the end result was no angle of attack protection, stall, and a fireball with lots of dead people.
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Proline
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Re: Qantas A330 Takes a Dive

Post by Proline »

Rockie,

Reading your posts about this airplanes systems is pretty humbling........You seem to have a huge amount of knowledge in this area.... Don't hold back because it's quite interesting. oh and one more thing...so say hypothetically I were to take control of this plane while the autgo pilot was on with no help from the crew would the avg joe be able to get this thing on the ground??? I fly currently fly a hawker XP.
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Rockie
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Re: Qantas A330 Takes a Dive

Post by Rockie »

Thanks proline, but my knowledge is no more than any pilot should have about their current steed. Your question is impossible to answer because you said "no help from the crew". If that were the case your best chance of landing the thing would be to turn off the autopilot, autothrust, flight directors, and ignore the airspeed bug. The systems are too complex for anyone to figure out without training (by complex I mean it does pretty much the same as your Hawker, but getting it to do what you want isn't intuitive without training) so the best bet would be to reduce the airplane back to its most basic, which as someone else has pointed out we should all be able to do. Then you just have to worry about configuring the airplane and deal with the size differential.
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Proline
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Re: Qantas A330 Takes a Dive

Post by Proline »

Funny after I posted this i was sitting in my hotel room and was thinking hell yes I'd get er down no sweat. Would be neat to try one out...who knows if AC ever starts hiring again I may very well. Who do you work for rockie?

Proline
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Rockie
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Re: Qantas A330 Takes a Dive

Post by Rockie »

The airline Canadians love to hate. Air Canada.
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Meatservo
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Re: Qantas A330 Takes a Dive

Post by Meatservo »

Meatservo not smart enough fly airbus. Meatservo stay in Otter, where belong.
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Chuck Ellsworth
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Re: Qantas A330 Takes a Dive

Post by Chuck Ellsworth »

Meatservo needs GPWS in Otter like dem Europeans must have.

Meatservo then get great erection as that voice prompt starts the count down from 500 feet.

Cat Driver got great erection when that voice started when doing a fam ride in Greek Otter last summer.

Cat Driver want GPWS in his Cub.......maybe keep Cat Driver from forgetting to flare for landing. :mrgreen:
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The most difficult thing about flying is knowing when to say no.

After over a half a century of flying I can not remember even one trip that I refused to do that resulted in someone getting killed because of my decision not to fly.
Meatservo
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Re: Qantas A330 Takes a Dive

Post by Meatservo »

Better than getting a great erection while doing a greek ride in a fam otter I suppose.
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Chuck Ellsworth
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Re: Qantas A330 Takes a Dive

Post by Chuck Ellsworth »

I have not had that experience, what was it like? :mrgreen:
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The most difficult thing about flying is knowing when to say no.

After over a half a century of flying I can not remember even one trip that I refused to do that resulted in someone getting killed because of my decision not to fly.
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