Originally Posted by
Lookleft
Dora-9 it was a post maintenance flight and yes we were flying without the benefit of hydraulics to the controls. In no way am I claiming to be an ace but LS certainly is as he has had to turn stab trim switches off therefore his knowledge of the 737 (and Airbus apparently) is absolute although he has never flown either and he still does not understand what MCAS does. He also doesn't seem to understand the difference between aerodynamic difficulties worked through on prototypes and pre-production aircraft that are subsequently certified and documented by the authorities and the MCAS system that was installed on an existing design with minimal oversight and deliberate obfuscation by Boeing. Boeing even went so far as to make a warning light that told the crew MCAS was operating an optional extra! I'm sure Sully is keen to chat to LS so that he can glean some crumbs of aviation knowledge that might fall from LS rather bloated table.
Lookleft,
With your superior knowledge of the B737 ( as opposed to other Boeing aircraft)
could you please explain to me how the MCAS keeps the stab running, if the two stab trim cutout switches have cut all power to the stab motors --- you have me really intrigued.
It is true I have never been endorsed on the B737, but I have a representative sample of Boeing products, and the basic design philosophy of the stab trim system has a family history dating back to the B-47.. I have also spent some years involved in technical development of Level D/D+ simulators, but that was all B737NG, not Max, so I am not unfamiliar with the B737 in general.
As for Captain Sullenberger, he did a magnificent job in ditching in the Hudson, placed in a near impossible situation, but nobody is perfect, he and his mate missed the ditching switch (whatever Airbus call it) , but that great effort and outcome does not make him an instant expert on all things aviation. Although the demands of the speaker circuit push him that way. It certainly does not make him an expert on certification of Boeing aircraft.
Hindsight is a wonderful thing, but having had a bit of experience internally with Boeing airworthiness people, I am certain they thought the way the aerodynamic characteristic that MCAs was directed at solving was a reasonable engineering solution at the time.
Tootle pip!!
PS:1 "----- LS certainly is as he has had to turn stab trim switches off therefor ------" You really are a twit --- are you suggesting that a normal response to a Non-Normal procedure is somehow to be criticised, because it hasn't happened to you. Given you aeronautical wisdom, suggest what we should have done, to avoid being classified as aces --- which traditionally means 5 or more combat victories. Perhaps you see dueling opinions on Pprune as some sort of moral (as opposed to mortal) combat.
PS2: If the B707 was to be certified today, it would need something like the MCAS, to prevent the pitch UP in the stall on Flap 50. "Back in the day", we coped.