Posted on 12/07/2011 9:55:38 AM PST by ventanax5
For more than two years, the disappearance of Air France Flight 447 over the mid-Atlantic in the early hours of June 1, 2009, remained one of aviation's great mysteries. How could a technologically state-of-the art airliner simply vanish?
With the wreckage and flight-data recorders lost beneath 2 miles of ocean, experts were forced to speculate using the only data available: a cryptic set of communications beamed automatically from the aircraft to the airline's maintenance center in France. As PM found in our cover story about the crash, published two years ago this month, the data implied that the plane had fallen afoul of a technical problem—the icing up of air-speed sensors—which in conjunction with severe weather led to a complex "error chain" that ended in a crash and the loss of 228 lives.
(Excerpt) Read more at popularmechanics.com ...
Sounds like a classic case of vertigo.
Poorly trained pilots stop trusting their instruments in stressful situations. Because they are unable to visually orient themselves, they get the sensation that they are falling, and instinctively pull back on the stick.
This is essentially what happened to JKF, Jr. back in ‘99.
Had this been a Boeing, the more experienced pilot would have sensed that the younger pilot was doing so.
Barky has a lot in common with Bonin, pulling back on the control in a death grip to raise taxes, increase drag, decrease lift, as our national 747 descends in a stall. Does it ever cross Barky's mind to push forward on the control once as an experiment and see if he gets a different result? Or is he so far in over his head he has only one trick. We've got a chance to pull out of this dive next November. Hopefully that's before impact.
Thanks for the ping. This is the best explanation I have seen, and by far the most complete.
BINGO! One of the first things military pilots learn in basic training is how to recover from stalls/spins - center the ball, nose down & reduce power until the wings start flying again (stall recovery) then add power and level off to stop altitude loss and maintain airspeed. Today’s Jr airline pilots spend 95% or more of the flight on autopilot and have basically forgotten how to hand fly their airplanes! Older, ex-military pilots still remember those basic skills/procedures even after decades have passed.
JC
AMEN!
JC
Sounds fishy to me. If electronics fail, you can’t see 5 degrees nose up, and why do that anyway? Just maintain level flight using the baro altimeter and set the recommended max range cruise power setting for a/c weight per the manual. Declare an emergency and request vectors to the nearest suitable landing field.
JC
I’m sorry too, but if Airbus/Air France continued to fly passenger aircraft with known or suspected defective air speed sensors, then they are P.O.S.s!!
I have quit flying commercially because I don’t trust air carriers to do adequate aircraft maintenance and pilot training, and refuse to be harrassed by those TSA thugs!
What’s the matter with you?
JC
In about 1 minute, eh? Sounds like the pilot in control trimmed it that way to “help” him hold it in a full stall all the way to ocean surface impact!!
JC
That is a stupid statement; very few of us humans manage to kill a large airplane’s entire passenger load due to ordinary, everyday “human error”!! SHEEEESH
JC
You just made up that crapola, didn’t you??
JC
Apparently they do have a method of determining their attitude after an electronic instrument failure.
There was no indication that the air speed indicators were defective, they were operating outside the design limits, limits that apppear to be imposed by the laws of physics. Some of the design decisions may have contributed to this tragedy, but the decisions do not seem to have been made to cut corners, or without sufficient deliberation.
Had they made different decisions, it might have averted this disaster, but caused others, perhaps worse. I remember in my undergraduate control systems course, the textbook authors described a decision to make an aircraft control system less responsive to pilot input, knowing that it might ocassionally lead to an avoidable accident. The reasoning was that the less responsive control would actually prevent many more accidents than the more responsive control system would prevent.
The Airbus has its drawbacks, but it appears to be a perfectly airworthy airframe with an excellent safety record.
Or buggy software trimmed the plane all by itself.
Gee, darn handy those black boxes were found. Pilot error. Go figger.
The part about JFK Jr. or Boeing?
We can tell you didn’t read the article. It’s interesting if you do. The biggest contributor to this accident was the one copilot that panicked and held the control stick all the way back most of the way down. A serious design flaw of the Airbus is the stupid idea of averaging the control inputs rather than have a switch to select which pilot is in command. Pilots have come to rely on the computers so much they now need a panic button to press to force the computer to take over when they lose control of the airplane. A panic button could have prevented this crash.
Tell me which part is crapola and I’ll tell you if I made it up.
Actually, I have a background in Aviation, though I am not a pilot. I repeated what was told to me by some pilots after JFK, Jrs. death.
“Apparently they do have a method of determining their attitude after an electronic instrument failure.”
That doesn’t answer the question of why 5 deg nose up. Depending on the airspeed, that could result in a significant climb rate.
JC
I didn’t say the A/S indicators were defective. The pitot tubes which provide input to the A/S had known problems for the model that was installed and Air France knew about it beforehand but were stalling on the changeout. I also didn’t fault the airframe. Regardless, the incident was recoverable but for bad piloting!
JC
That is possible also, but I would think much less that a minute’s elapsed time for the change. Or maybe not, automated control systems don’t get tired like humans and need the trim to reduce the force required to maintain a selected control input. I used to instruct instrument flying and occasionally had to “train” a student to use a light touch by setting very high, unusual trim tab inputs and have the student fly straight & level, maintaining altitude and heading until his arms and legs began shaking...then I allowed him to trim the forces out. Most weren’t “ham-fisted” after that and became much better instrument pilots.
JC
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