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Old 11th Mar 2019, 16:36
  #388 (permalink)  
indigopete
 
Join Date: Feb 2007
Location: Glasgow
Age: 55
Posts: 24
Originally Posted by Sunfish View Post
Now is probably a great time to buy Boeing shares. I have rarely seen such utter tripe talked over two accidents that look, at least at first glance, to be caused by sub standard pilots getting caught by the same tricky but surviveable system failure. Read the 3$%^&ing Boeing AD! Another reason to stop putting undertrained muppets in airline pilot seats.

That might be true but these accidents have sure stoked a lot of legitimate debate about the role of software in flight control. It used to be you had an autopilot and it was either on or off. Now it can be "on" even when it's off if the logic decides the PF requires a "bit of assistance" - leading in some cases to the proverbial "wtf" adverse reactions from the manual input dimension.

In the case of MCAS it looks to me to be a victim of the success of the 737's longevity. It's probably the most versatile airframe ever built having survived 50+ years of power-plant evolution, geometrical stretching, role revision and load growth (GTWO has not-far-off doubled I think since the 100).

Then along comes the straw that breaks the camel's back - a couple of engines that really required a new airframe design to get properly certified with comfortable aerodynamic margins. But such is the versatility of software these days that any shortfall in aerodynamic completeness can be handily compensated for. So in a competitive environment it inevitably happens. Doesn't mean you can't have lots of software doing useful stuff with a solid aircraft design, it's just that it should'nt be doing the airframe's job IMO to an extent that it's a weak link.

Looking at that hole in the ground posted earlier on (if the pic is legit) is positively hair-raising. Although we are speculating (it is a "rumour network after all"), the only times I've seen anything like that is if a wing is shot off or something/one has forcibly pointed the nose at the ground and applied full throttle since aerodynamically stable craft generally always have some horizontal component of velocity regardless of what you do to them. Even Lockerbie had a semblance of a detectable hull left after it fell 30,000+ feet.

Not saying there isn't some unrelated cause that's nothing to do with the discussions here. Just saying there is a strong engineering and philosophical case (IMHO) for not doing what Boeing did with the Max and sellotaping over geometrical design deficiencies with software.

Last edited by indigopete; 12th Mar 2019 at 09:45.
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