Air France stalls another one

I thought that was supposed to be one of the advantages of the Airbus system that you could just hold the controls to the stops and the plane would take you to the max performance of that envelopes edge?
 
Henning said:
I thought that was supposed to be one of the advantages of the Airbus system that you could just hold the controls to the stops and the plane would take you to the max performance of that envelopes edge?
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Yeah, but do you really want to fly final at the ragged edge of the stall?
 
AND, the title of the thread is misleading. The airplane did exactly as it was designed to do and PREVENTED the stall.
 
Greg Bockelman said:
Yeah, but do you really want to fly final at the ragged edge of the stall?
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Depends where along final. If I am high on final with passengers, yes, that is exactly what I do as the plane drops like a rock and the pax don't even notice rather than a slip that freaks everybody out. As I get on glide path for a good landing I lower the nose or add throttle to get my flare energy back.
 
Henning said:
Depends where along final. If I am high on final with passengers, yes, that is exactly what I do as the plane drops like a rock and the pax don't even notice rather than a slip that freaks everybody out. As I get on glide path for a good landing I lower the nose or add throttle to get my flare energy back.
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Your passengers don't notice the stall warning?

Or are you really not that close to a stall?
 
I'd much rather slip. My passengers are freaked out anyway. :D

Plus it's safer.
 
MAKG1 said:
Your passengers don't notice the stall warning?

Or are you really not that close to a stall?
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Depends on the airplane, airfoil design and wing loading. Some will start sinking fast well before the stall warning sounds. This should be the case with an airliner. However if you get the stick pusher, (the airplane got down to 700 AGL :eek:) you've gone way too far and from that altitude a go-around is the prudent thing to do.

Generally low wing loading airplanes with fat wings don't sink too much.
 
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Henning said:
Depends where along final. If I am high on final with passengers, yes, that is exactly what I do as the plane drops like a rock and the pax don't even notice rather than a slip that freaks everybody out. As I get on glide path for a good landing I lower the nose or add throttle to get my flare energy back.
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At an actual stall, or at an airspeed on the backside of the power curve but with no power? That works to drop altitude in a hurry.

(I think I'd rather slip too, that close to the ground)
 
Sac Arrow said:
At an actual stall, or at an airspeed on the backside of the power curve but with no power? That works to drop altitude in a hurry.

(I think I'd rather slip too, that close to the ground)
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Just close is fine, the Airbus DID NOT stall.
 
Henning said:
Depends where along final. If I am high on final with passengers, yes, that is exactly what I do as the plane drops like a rock and the pax don't even notice rather than a slip that freaks everybody out. As I get on glide path for a good landing I lower the nose or add throttle to get my flare energy back.
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Sounds like adapting short-field technique to me. What's the big deal?
 
Henning said:
Just close is fine, the Airbus DID NOT stall.
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No, its protection systems prevented that.

Regardless, if the crew had managed to make the runway on the ragged edge of a stall, they'd be sinking fast and have no extra airspeed with which to flare.

In your cessna you can bring the speed back just above stall speed, get a nice sink rate going, then at 100 agl dip the nose down and pick up a little extra speed to slow sink and use in a flare.

I'm pretty sure that was not the intention of the airbus pilots.
 
Greg Bockelman said:
AND, the title of the thread is misleading. The airplane did exactly as it was designed to do and PREVENTED the stall.
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Good point - that is true, the airplane did protect itself from inattentive pilots.

FWIW, the problem is not limited to Air France pilots.....word on the street is that a PSA RJ got a stick shaker within the last month while climbing through the flight levels - resulted in dual flameout. Unlike the Pinnacle guys, that crew managed to get one relit on the way down.

I guess that is one positive thing that can be said about the Bus.
 
dell30rb said:
Depends on the airplane, airfoil design and wing loading. Some will start sinking fast well before the stall warning sounds. This should be the case with an airliner. However if you get the stick pusher, (the airplane got down to 700 AGL :eek:) you've gone way too far and from that altitude a go-around is the prudent thing to do.

Generally low wing loading airplanes with fat wings don't sink too much.
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Maybe just a high wing loaded swept wing thing, but I actually like the wing waggle technique. Basically controlled small dips of the wings, which cause a momentary increase in descent rate without really causing any sort of turning/yawing moment. You can keep the power up (thus negating spool time), but still make controlled incremental corrections for glideslope. Probably not something passengers would enjoy though. And I'm not seriously suggesting that someone do this in a transport category jet, just that there are other options aside from chopping the throttles and getting on the backside of the pwr curve, or slipping.
 
dell30rb said:
Depends on the airplane, airfoil design and wing loading. Some will start sinking fast well before the stall warning sounds. This should be the case with an airliner. However if you get the stick pusher, (the airplane got down to 700 AGL :eek:) you've gone way too far and from that altitude a go-around is the prudent thing to do.

Generally low wing loading airplanes with fat wings don't sink too much.
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What stick pusher? Are you talking Airbus or Boeing here?
 
Henning said:
Depends where along final. If I am high on final with passengers, yes, that is exactly what I do as the plane drops like a rock and the pax don't even notice rather than a slip that freaks everybody out. As I get on glide path for a good landing I lower the nose or add throttle to get my flare energy back.
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If you are talking in Airbus terms why would you have been out of auto thrust on final?
 
dell30rb said:
No, its protection systems prevented that.

Regardless, if the crew had managed to make the runway on the ragged edge of a stall, they'd be sinking fast and have no extra airspeed with which to flare.

In your cessna you can bring the speed back just above stall speed, get a nice sink rate going, then at 100 agl dip the nose down and pick up a little extra speed to slow sink and use in a flare.

I'm pretty sure that was not the intention of the airbus pilots.
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All this should be played out WELL above 100'.
 
dell30rb said:
No, its protection systems prevented that.

Regardless, if the crew had managed to make the runway on the ragged edge of a stall, they'd be sinking fast and have no extra airspeed with which to flare.

In your cessna you can bring the speed back just above stall speed, get a nice sink rate going, then at 100 agl dip the nose down and pick up a little extra speed to slow sink and use in a flare.

I'm pretty sure that was not the intention of the airbus pilots.
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With all systems working normally you wouldn't be on the ragged edge of a stall.

From the Airbus FCOM:

GROUND SPEED MINI FUNCTION PRINCIPLE The purpose of the "ground speed mini function" is to take advantage of the aircraft inertia when the wind conditions vary during the approach. It does so by providing the flight crew with an adequate indicated speed target. When the aircraft flies this indicated speed target, the energy of the aircraft is maintained above a minimum level ensuring standard aerodynamic margins versus stall. If the A/THR is active in SPEED mode, it will automatically follow the IAS target, ensuring an efficient thrust management during the approach. The minimum energy level is the energy level the aircraft will have at touch down if it lands at VAPP speed with the tower reported wind as inserted in the PERF APPR page. The minimum energy level is represented by the Ground Speed the aircraft will have at touch down. This Ground Speed is called “GROUND SPD MINI”. During the approach, the FMGS continuously computes the speed target using the wind experienced by the aircraft in order to keep the ground speed at or above the “Ground Speed Mini”. The lowest speed target is limited to VAPP and its upper limit is VFE of next configuration in CONF 1, 2, 3 and VFE-5 in CONF FULL. The speed target is displayed on the PFD speed scale in magenta when approach phase and managed speed are active. It is independent of the AP/FD and/or A/THR engagements. Wind is a key factor in the "ground speed mini function".
 
Henning said:
All this should be played out WELL above 100'.
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Yes, well depends on the airplane. In an airbus 700 is way too low.

The only plane i've really played around with this in much is a cub. Slipping vs slowing down/ speeding up to 'play' a power off 180 glide to hit a spot on the runway
 
dell30rb said:
Yes, well depends on the airplane. In an airbus 700 is way too low.

The only plane i've really played around with this in much is a cub. Slipping vs slowing down/ speeding up to 'play' a power off 180 glide to hit a spot on the runway
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Play with it in a higher wing loading plane, small changes in speed behind the power curve have a more dramatic effect.
 
Fearless Tower said:
FWIW, the problem is not limited to Air France pilots.....word on the street is that a PSA RJ got a stick shaker within the last month while climbing through the flight levels - resulted in dual flameout. Unlike the Pinnacle guys, that crew managed to get one relit on the way down.
Click to expand...

So flame out from too high AOA? Not seeing the direct link anyway.
 
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