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BA 747 crew commended for escaping near-stall on take-off
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) المزيد...Sort type: [Top] [Newest]
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.)
@ 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.)
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)
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)
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...
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.
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.
porterjet both your comments are right on the mark!