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Old 22nd Mar 2019, 09:07
  #2313 (permalink)  
Uplinker
 
Join Date: Nov 1999
Location: UK
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Originally Posted by Smythe
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[It is amazing the amount of Boeing bashing on this forum. Boeing has made tens of thousands of safe & efficient airliners for more than half a century & that's why there are more Boeings than anything else.]

They pushed the MAX too far, a quick band aid to counter the neo.

A software fix to counter an unstable platform...

tale of the tape...why is MCAS required for certification?
In my humble opinion, they should have started again with the 73 about the time of the -300/-400 and completely redesigned it. As it stands, they seem to have cobbled together systems as they became available or desirable and bolted them where they could find space. (The “computer fuel summing unit” - can’t remember its exact name - is fixed outboard above the F/Os head - why not in the avionics bay?). The F/Os seat cannot be moved vary far back because of the C/B rack behind it. The elevator feel unit has its own pitot probes each side of the fin.

I only have experience of the -300/-400, but that aircraft is a mish-mash of mechanical and electronic devices, seemingly not properly integrated, but just about working. The ‘Classic’ autopilot does not trim ailerons or rudder, so when you take out the autopliot you often have to spend a mile or so on short finals getting the thing trimmed. The Cockpits of the -300/-400 look as if they were “designed” by firing a shotgun at a blank panel, and fitting the instruments and indicators whereever there was a handy hole. Generators have to be manually switched on to the buses. Later models without the round generator dials, still use the old panels with the cut-outs for the round dials rather than making a new panel....how cheap is that?

It seems to me that as each new requirement or problem came along, instead of doing a redesign, Boeing developed a standalone fix or widgit to solve the problem - but they don’t appear to have always thought it through in terms of the way the whole aircraft works, or how the pilots would interface with it.

As to why the 73 is so popular, I think South West have a lot to do with that, (they are also indirectly partly responsible for the arrested development of the 73). I have been told that Boeing also have some very creative fleet purchasing schemes for airlines.

As to MCAS, instead of affecting the THS trim, why not simply have it modify the elevator feel at hiigh AoA - which is, after all, the problem caused by the engine nacelles. Or insert a gentle down input to the elevators? But not the trim. Secondly, why have only one AoA probe, or even two? For such a critical device, why not have five?











Last edited by Uplinker; 22nd Mar 2019 at 10:01.
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