Air Asia Indonesia Lost Contact from Surabaya to Singapore
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If the 'Air Crash investigation' reconstruction of these 2 accidents are to be believed I think you will find that they were contributed to, significantly, by the automatic systems doing what they thought was correct, but due to a few swiss cheese holes proved to be in error of what was required.
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Air New Zealand Airbus crash in the Mediterranean (Perpignan) 2008, seasoned German & NZ crew, including engineers, no one understood, until too late.
With all due respect Mr. Geek.
If it had been a Boeing non FBW, even with the frozen AOA vanes, it would have just recovered and flown away. The crash occurred because the computers got in the way and changed the control laws 2 or 3 times (Sorry, I last read the accident report a few years years ago so I don't remember the exact sequence.)
A clear case of "Loss of Control-Unrecognized or Not Understood Control Configuration Change."
Air New Zealand Airbus crash in the Mediterranean (Perpignan) 2008, seasoned German & NZ crew, including engineers, no one understood, until too late.
This one goes beyond pilot error into the realm of utter stupidity.
Functional test of alpha protection. The test instructions are very clear that the test MUST be conducted at 14000 ft and not less that 10000 feet AGL. Deliberately stall the aircraft to confirm that the alpha protection prevents the stall. Anyone who tries this at low level is way beyond stupid and certifiably insane. They did it at low level. DUH.
Functional test of alpha protection. The test instructions are very clear that the test MUST be conducted at 14000 ft and not less that 10000 feet AGL. Deliberately stall the aircraft to confirm that the alpha protection prevents the stall. Anyone who tries this at low level is way beyond stupid and certifiably insane. They did it at low level. DUH.
If it had been a Boeing non FBW, even with the frozen AOA vanes, it would have just recovered and flown away. The crash occurred because the computers got in the way and changed the control laws 2 or 3 times (Sorry, I last read the accident report a few years years ago so I don't remember the exact sequence.)
A clear case of "Loss of Control-Unrecognized or Not Understood Control Configuration Change."
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Do you honestly believe that a Boeing can recover reliably from a low level stall ?
They are aircraft that have been designed and tested to recover.
Even the XL airways recovered from the stall nicely only to be sabotaged by a change from Normal Law to Direct Law, then to Abnormal Attitude Law. Problem was, the trim was already cranked full nose up by the system as they approached the initial stall. It was the excessive nose up trim that caused the loss of the aircraft. (Maybe a warning system is required as you approach full nose up?)
Your question should really be do I really think every ATPL rated pilot can recover from a stall? On that count, we have seen too many failures.
Boeing
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Somebody is forgetting about Turquish B737 approaching Schiphol or Asiana B777 approaching SFO.
On the Turkish B737:
What do you expect to happen when the autothrottles pull the throttles to idle on an above the glideslope approach-but not for the reason you would expect.
By the time the crew finally realized they had a problem and forced the throttles up, it was almost too late. When the autothrottles then snatched the throttles back again, it was too late.
You have to watch your airspeed on approach. You really cannot delegate all the responsibility for watching your airspeed to the systems. You must monitor and control airspeed. Insufficient power on approach means you are going to be landing short. Same goes for Asiana's 777. Different reasons for insufficient power, but same short landing result.
These were not primary stall accidents, even if the crews got to some high AOA in attempt to buy air time.
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In XL 888 crash, the FBW changed law from normal to direct, because landing gear was down. The THS was at max. nose up position in manual mode. The elevator moved accordingly to sidestick input, mostly full ND, but couldn't counter-react the pitch up moment. The FBW switched to alternate for landing gear up. Intersting is the alternate law behaviour with elevator movement in opposition to sidestick input - reference Final report, FDR graph in page 113.
In conclusion, good luck with improving the "manual flying skills" in alternate law.
In conclusion, good luck with improving the "manual flying skills" in alternate law.
Originally Posted by The Ancient Geek
Do you honestly believe that a Boeing can recover reliably from a low level stall ?
One NG, one classic.
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The trouble with using very advanced systems to make flying easier, is that they degrade the very skills that you desperately need for when those same advanced systems fail.
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The point that strikes me from reading the report a few times is that having seen the reset on ground procedure it was "felt appropriate" to try it airborne .. now thats a no-no for line flying.
That and the failure to bring the units online again by pushing the reset buttons to regain dark cockpit, then add the stick back stall recovery !!
And where was the crew brief before the cb pulling started ?
It's very simple to blame the architecture and turn this into a A vs B slanging match, but really ... the aircraft and it's occupants should have survived, and it would appear that human intervention prevented that.
That and the failure to bring the units online again by pushing the reset buttons to regain dark cockpit, then add the stick back stall recovery !!
And where was the crew brief before the cb pulling started ?
It's very simple to blame the architecture and turn this into a A vs B slanging match, but really ... the aircraft and it's occupants should have survived, and it would appear that human intervention prevented that.
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Please enough with the AvB slagging contest!
Sometimes things go awfully bad. In some planes they go bad because they lose a prop blade. Does this mean we should start beating on turboprops because "jets don't have props"?
Nah, come on peeps. Meddling with the CBs in the middle of the flight was never, has never been and will never be a good idea, something pilots MUST have learned at least since that bad bad crash in the US many moons ago. The one where they pulled a CB to prevent unwanted noise, but that also meant they tried to take off with no flaps or anything. One single survivor - the rest was carnage.
I would suggest you ponder about what Machinbird said. Maybe there needs to be another category of accidents: "Loss of Control-Unrecognized or Not Understood Control Configuration Change."
The Kazan 737 crash would probably be a candidate for this. Very low level stall, nose dive, all caught on camera. You really should take your beta blockers before watching that video.. *joke*
Sometimes things go awfully bad. In some planes they go bad because they lose a prop blade. Does this mean we should start beating on turboprops because "jets don't have props"?
Nah, come on peeps. Meddling with the CBs in the middle of the flight was never, has never been and will never be a good idea, something pilots MUST have learned at least since that bad bad crash in the US many moons ago. The one where they pulled a CB to prevent unwanted noise, but that also meant they tried to take off with no flaps or anything. One single survivor - the rest was carnage.
I would suggest you ponder about what Machinbird said. Maybe there needs to be another category of accidents: "Loss of Control-Unrecognized or Not Understood Control Configuration Change."
The Kazan 737 crash would probably be a candidate for this. Very low level stall, nose dive, all caught on camera. You really should take your beta blockers before watching that video.. *joke*
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Torqued: Air Asia Crash Highlights Risks of In-flight Troubleshooting | Business Aviation: Aviation International News
Air Asia flight turns around after 'technical issue' - CNN.com
The other significant lesson from this crash is related to maintenance. There were repeated write-ups and deferrals of the rudder trim limiter system. The accident report does not delve into why this was allowed to occur and why the aircraft was not taken out of service until the problem could be found. Repeat items have to be dealt with in a timely manner and not deferred over and over so that crews are not put in the position of having to deal with known problems.
