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NTSB: Asiana 777 commanding pilot assumed auto-throttles were maintaining speed
The pilot in command ofAsiana Airlines Flight 214, the Boeing 777-200ER that crashed on landing at San Francisco International Airport (SFO) July 6, told investigators that he assumed the aircraft’s auto-throttles were engaged and maintaining a speed of 137 knots as the 777 came in for a landing. The aircraft’s speed dropped to just 103 knots at the time of impact.
The commanding pilot was one of three pilots in the cockpit at the time of the crash, sitting in the right seat. He was serving as an instructor for the pilot flying the aircraft, sitting in the left seat, who was in the midst of training on the 777 after serving for eight years as an Airbus A320 captain for Asiana.
“At about 500 feet, [the commanding pilot] realized they were low,” US National Transportation Safety Board (NTSB) chairman Deborah Hersman said at a Tuesday news conference in San Francisco. “He told the [flying] pilot to pull back.”
The commanding pilot told NTSB he realized a go-around was necessary and noted the flying pilot had already pushed the throttles forward. But it was too late; the aircraft’s main landing gear was the first to impact SFO’s sea wall as the 777 came down short of runway 28L, Hersman said. The tail section then hit the sea wall. The aircraft “went into a 360 degree spin,” she added.
Debris from the crash, in which two passengers were killed, can be seen from the sea wall all the way to where the aircraft came to a stop, Hersman said. “Sections of the cabin are found very early on in the debris field,” she noted, pointing out that aircraft parts, galley materials, newspapers and magazines are scattered throughout the debris field.
http://atwonline.com/safety/ntsb-as...assumed-auto-throttles-were-maintaining-speed
dal sito sopra postato ho estrapolato questi due commenti forse interessanti, che ne pensate?
il primo:
his raise another issue of cross training on different philosophy of Airplanes. The Airbus has anti stall protection on the for of alpha floor (the stall speed) the auto throttle command a automatic maximum thrust available on the engines and force the pilot flighting to take actions and correct the problem. It will continue on this new setting until it is physical remove from it. This is a safety thing from Airbus, yet it still can kill you (Air France accident over the south atlantic).
The biggest concern here is Why the Pilot Instructor did not command a go around with plenty of time to execute a safe one and return to a safe landing.
All the passengers and crew have to thank whoever is their God is because this was not a survival crash when you see the event and how the airplane turn 360 degree. The airplane for all purpose was intentionally flown to the ground. Praises for Boeing for building a tank of an airplane.
risposta al primo:
The 777 has the same (similar) stall protection, but if you DISARM the A/T system the only warning that 'pops'out is SPEED LOW and then the stick shaker.
In this situation there is 'too-many' assumptions on this very dangerous situation. Definitely they were NOT STABLE by a 1000 feet, even if the A/T system was DISARMED, if they were 'STABLE' the amount of thrust they would need at 1000 feet on a STABLE condition, would suffice to land safely the A/C.
I can understand the problem of a pilot coming from an Airbus to a Boeing environment, it takes time, what I cannot understand is the 'Instructor' not being aware of this little issue and not being able to 'be' ahead of the aircraft and anticipating the problem and REACT immediately instead of advising the other pilot that obviously is not aware of what's happening. This all situation looks, to me, that 'AWARENESS" was very low on this cockpit.
In the other hand, to 'recover' from a Stick Shaker and DO a Go-Around is not an easy task. Since the A/C was low and on the Landing Configuration, I can believe that the thrust levers were at idle (full idle) and it takes 7 to 9 seconds to reach Go-Around power after pressing the TO/GA buttons (normally helped by pushing FWD the thrust levers). And they didn't had the 'time'.
It's a sad day, fortunately, despite the injuries, only few died.