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Old 6th Jul 2011, 03:34
  #849 (permalink)  
PJ2
 
Join Date: Mar 2003
Location: BC
Age: 76
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HarryMan;
Only by being very open about the crew's cockpit experience, and their response - what was expected and what came naturally, can we further improve the modern 'cockpit flight centre' by integrating the best of both worlds.

Like the last UK Govts attempt at a 'truly joined-up government policy', the dots might all be there, but most are still quite some way from being even crudely connected, let alone integrated as a comprehensible, efficient and finely optimised cockpit for flight control.

It seems inevitable that mistakes were made in many areas of design as well as pilotage; even at this early stage it worries me that justifying them (individually) is quite possible, but never as a joined up whole for safely governing an aeroplane's flight under extreme and singular conditions.
Yes, I think so. Each paragraph in your post has something important to say about the change, or rather "the shift", but your last paragraph is exceptionally important, the justification being economic.

The traditional controls (even the stick) are a concession to history, but in truth, because it is all digital, the thrust levers, (for example) could have been four push-buttons (for each detent) or sliding dimmer switches. The "cultural" collision has been between the necessary ultra-conservative, (as in extremely slow to change/alter familiar controls which we operate on an entirely sub-conscious level) and the entirely new developments in control (with a bow towards ergonomics) made possible by reliable, light-weight chips and wires. (I do not mean to downplay here the complexity and vision of the concepts which underlie the design).

The failure hasn't been in the concept and resulting design but in the lack of anticipation of the philosophical change in "world view" from the cockpit with regard to very specific technical tasks, right down to the practical "how do it know?" puzzlements of crews brand new to the airplane. Your comment regarding "being open" means (and meant) to me that if one didn't like what it was doing, one disconnected it and flew it like a DC9 or a B737. My 15-year experience reified that view completely.

One just simply didn't accept that this airplane, any airplane, couldn't be stalled and so flew it with the same respect and knowledge one had for the boundaries of controlled flight and certification limits as one always had with one's aircraft. It doesn't take much observation to see that that understanding has changed over the years.

In early years of "the shift" however, it wasn't "more of the same" in the sense that the shift from piston-to-jets, straight-wing to swept wing, mid-altitude to high altitude flight took beginning in the late 50's was still with a conventional cockpit with conventional controls. The accidents were due to slower acceleration (engine and therefore airplane rates - no big 'wash' over the wing from the props, - higher weights, higher altitudes where yaw dampers and Mach number meant something, an extremely clean profile, and the effects of buffet boundaries never encountered in piston flight.

Indeed, if one is entirely open it can be successfully done and to a very large extent, has, as the accident data has borne out. The other side of "the shift" is reading into the design and the aircraft, more complexity than is there which leads to second-guessing and out-guessing the solutions to the problems of flight, which, as gums consistently discusses so well apropos his fighter experience, still are new to transport aircraft. Despite the complexity underlying the relative simplicity of the cockpit, the airplane remains an airplane when one "looks through" the levels of automation. Despite minor disagreements, BOAC's and NoD's comments, as I have read them, reinforce this important notion. In this accident, I think that there is very rich learning for those well beyond and upstream of the cockpit.

Last edited by PJ2; 6th Jul 2011 at 03:50.
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