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BA 747 crew commended for escaping near-stall on take-off

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South Africa's Civil Aviation Authority has praised the airmanship of British Airways Boeing 747-400 pilots who battled to prevent a low-altitude stall after the leading-edge slats unexpectedly retracted during lift-off from Johannesburg. (www.flightglobal.com) 기타...

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OldCabanaGuy
"the CAA says the crew had "no notion" that the slats had retracted before rotation. There is no separate indication in the cockpit for leading-edge slat position."

Why is this so? Better yet, why can't a $250 million aircraft provide video of external flight control and undercarriage componenets?
lsh2429516
lsh2429516 0
Well, unlike Airbus panel, where there is actually notion of the flap's current position and the position that crews choose, there is only one plane in the Boeing that has that kind of gauge: B777 and only plane with external camera, used for taxing. If I am remembering correctly, B747's slats are supposed to retract when the reverse is engaged. Cabin Crews said that the engine gauge showed two of the engines, engaged in reverse, which it means the computer did the right thing, pulling up its slats. One I am concerned is that why reverser was engaged when the plane took off....
lenharvey
Len Harvey 0
I think the only thing we should concern ourselves with is not weather the pilots had cockpit or visual evidence of what was happening to the slats, but that the imminent stall of the massive aircraft on its take off-roll was handled safely and correctly..Its for the CAA and the Aircraft manufacturers to debate the wisdom of Fly by Wire.
Jkinane
I was a mechanic on 747-400's in the early 90's and I thought there were flap/slat position indicators displayed on a CRT with a pictoral display of the aircraft. Maybe it was on a maintenance page of the EICAS.
Jkinane
I was a mechanic on 747-400's in the early 90's and I thought there were flap/slat position indicators displayed on a CRT with a pictoral display of the aircraft. Maybe it was on a maintenance page of the EICAS.
Jkinane
I was a mechanic on 747-400's in the early 90's and I thought there were flap/slat position indicators displayed on a CRT with a pictoral display of the aircraft. Maybe it was on a maintenance page of the EICAS.
19birdman38
What contributed in no small measure to the safe outcome is the pilot flying (PF) going back to basics of "stick and rudder." It takes nerves of steel to put the nose of a heavy aircraft down to gain airspeed so close to the ground. And having the non-flying pilot call out altitudes was a great decision! "Ballsy" moves on everybody's part!
porterjet
porterjet 0
Rule # 1: fly the airplane.
porterjet
porterjet 0
I don't know if there is a separate slat indication but it is academic. At 6 feet above the runway with the stick shaker going off you are not looking at gauges.
19birdman38
Great comments, porterjet!
Jetster99
How did they not know the flaps were down before rotation???
GeoMedic
GeoMedic 0
Infomation I saw on aviationherald indicated that the mechanism was at the rear-most travel position and the sensor had been set a little ahead of that. Sensor triggers automatic retraction.
porterjet
porterjet 0
The flaps/slats were set before takeoff, as Bill says a sensor misread the thrust reverser position and the way the system works it assumes you have either landed or aborted the takeoff and retracts the slats so blowback air from the reversers does not damage them.
glas1rg
Good job of doing what they were trained to do. Too bad these aircraft can not be equipped with VIDEO DATA RECORDERS to document this type of occurance for other training purposes, and film several areas of the aircraft to see what happened and effect a fix.
houseofstout
L. Stout 0
The good news of this is the pilot and co-pilot flew the aircraft and not the instruments.
Dannoga
I also thought there was an EICAS indicator page/screen showing deployment of slats/flaps...but the more I think of it I think slats were not on the config profile. Great job flying 1st!
Katie019
completely agree Jim, and porterjet you are spot on.. 'aviate, navigate, communicate' :)
THOSDICK
I salute the pilots for a job WELL DONE-BRAVO. I agree with Katie,and Porterjet - Fly The Airplane.
THOSDICK
I salute the pilots for a job WELL DONE-BRAVO. I agree with Katie,and Porterjet - Fly The Airplane.
WigzellRM
"Better yet, why can't a $250 million aircraft provide video of external flight control and undercarriage components?"
External videos should have been implemented long ago and probably would have saved many lives already.
Bravo to the crew for flying the plane and not relying on the computers. Over reliance on automation has cost many lives already.

lsh2429516
lsh2429516 0
Well, "someday" FAA will implement the new rule saying all commercial a/c must be fitted with external camera that will able pilot to see all the part of a/c.
pamuth
Excellent job by the flight deck! Fly the airplane first, then figure out what happened. They don't have time to be checking video displays while the aircraft is struggling just after rotation.
airblitz
Elvin Zhou 0
Whether there is a camera or not is not important. It wouldn't have mattered that much for a stall 30 ft off the ground. I mean it's great the crew decided to fly the plane instead of yelling for help over the radio or trying to determine which part of the plane failed...
PlELOT
PlELOT 0
Please read the actual article/report.. it provides many insights !

1) The crew flew the plane first and made the right decisions, with successful outcome resulting - good
2) The crew had no idea what was wrong with the plane (slats retracted) and took instinctive action based on limited information - bad
3) Uncommanded slat retraction taking your airplane into a stall regime - bad
4) Boeing's SB will hopefully prevent it from happening again, by removing the faulty design logic - good
5) In the past, situations where highly trained crews did not know what was wrong with the plane, have resulted in crashes, regardless of the amount of skill (AA Flight 191, for one, a complicated case)

In conclusion, it is always better if the crew KNOWS what is wrong with the plane, to the extent possible (Hey captain, the slats have retracted! ~as opposed to~ Hey captain, the stick shaker is going off and I have no idea why!) Both cases require flying the plane, yet, in the first hypothetical situation the pilots would know exactly what and why is happening, and what they needed to do. In the second, actual situation, they made the right decision, but they did not know what was happening, and if it was the right decision at the time. One cannot predict all possible situations, but an uncommanded slat retraction must be avoided at all costs, or the pilot warned in a manner that is impossible to miss, if it does occur. Contributing to the situation was the fact that the logic of slat retractions was simply tied in to thrust reversers actuation without taking anything else into consideration (airspeed, the fact that the plane was flying, many other factors)
lsh2429516
lsh2429516 0
I first apologize if this sounds like I am trying to pick up a fight but I am not trying to do that.

@ Elvin: As plane was taking off from “hot and high” environment, plane needs to get much more airspeed than what it would required on sea level. Stall 30 feet above ground sound like not much of a deal when the plane is also at 30 feet above sea level but in this case, the plane was 5,600 feet above sea level (according to not-so-trustworthy-wikipedia) which it meant that stalling plane at that height might have resulted in lose of total lift and result in death of hundreds of people.

Hope this makes sense.

(Pleas feel free to fix any information if I am wrong.)
AerodexdotCom
JW Hart 0
I always love reading the "Monday morning armature aviation quarterbacks" 2nd guess what they read in an incomplete media story, always entertain. :)
porterjet both your comments are right on the mark!

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