DC-ATE :
The Toronto accident was pilot error. The F/O actuated the spoilers 60' above ground on a DC-8.....strickly a NO, NO!
On a 'Bus ( for instance), the ground spoilers would not deploy in an in-flight configuration, and in an
alpha prot situation, the spoilers would have been retracted.
And btw, the co-pilot was only arming the ground spoilers, not extending them.
Lake Pontchartrain was an apparent failure of the PTC.
Wrong : the PTC had been MELed and was inoperative on that flight. The elevator position was from crew action (manual wheel).
The JAL DC-8 crashed in Moscow because of -another- spoiler extension just after takeoff, causing the AoA to increase beyond stall.
As to my remark, or my question, rather, it still stands : Are these accidents related to flight controls or not ?
Christiaanj
Fundamental confusion between FBW - fly-by-wire - as a concept, and what has been added since.
FBW as such has nothing to do with stall protection, etc.
Sorry, Christiaanj, you can't dissociate the concept of FBW and the safety aspects it brought to our industry
because they are at the heart of this discussion, some claiming their distrust of the concept, others with a different agenda. As a matter of fact, the protection concept appeared right at the beginning of the A300 test bed electrical signalling study : they were the natural inherent progression of the initial design. That Boeing chose a different path for its projects belongs to another discussion.
I have been flying the 'Bus for thirteen years now, after some experience on classic hydraulic-boosted flight controls - and some cable-and-pulleys- types and I've found the electrically signalled flight controls to be far superior, in terms of comfort, ease of flying, accuracy and safety.
This term of safety needs to be elaborated on a bit further : People only think of safety through the envelope protection of the different FBW realisations...OK, but the qualities I've eluded at also participate : flying with an always in-trim aircraft, with exactly the same perceived respone whatever the configuration or the speed takes a lot out of one's mind, making one quite a bit more available for the main task of flight management.
Please note that on my previous post I was already disputing the title of the thread, which should be more about flight deck automation -and its ultimate realisation : the FBW, envelope-protected airliner- rather than just replacing mechanical links with a bundle of electrical wires.
In those days we had stick shakers, stick pushers and suchlike, as stall protection. Which you could ignore at your own discretion.... if you knew what you were doing.
The problem goes far beyond that as there are moments when the task at hand exceeds one's capabilities : think of all the instances of windshear-caused accidents. Are they pilot errors ? Now compare the last instants of these cockpits with a "
WINDSHEAR TOGA" maneuver in a 'Bus...didn't we make some real progress here by providing the guy in charge with an easier/safer tool which gives him the full maneuvering capability of the FBW system ?
All that said, I'm not naive enough to think for one second that FBW is the ultimate panacea and that it did not introduce a few traps in flying...Most of them are human factors-related : what confidence in the system, what about trust, what about complacency, and human-machine integration ?
I for one don't take anything for granted. I'm certainly not the only one around.
Onthat aspect, this study deserves some careful reading as it goes a lot beyond the "if it's not a DC-3, I won't take it"- type of argument :
Perceived Human Factor Problems In Flight-Deck Automation