Originally Posted by
Klsytakesit
It will come down to certification basis.
Boeing, at the request of SWA, Alaska Airlines and to a varying degree the big Three, rushed out a response to the A320/321 NEO.
In doing so they discovered that a big under-slung engine on a longer pylon created deleterious effect on maneuver margins near the edge of the envelope. Lacking any type of an intelligent maneuver-assistive FCC they strapped one on to essentially a manual system. And broke all their own rules about critical Flight Control design. Single source, no fail-safe, no comparator, no false-input control. Nothing but a QRH. Having pushed up against the limits of simple common type, they and their airline partners convinced the FAA that these changes were simple and not only did not require training but really only mechanics need know of them. No need to point it out to pilots as it would just confuse them. Nothing should happen and if it does it will be hidden under the general Runaway Stabilizer Trim QRH...
Bingo. Forget about MCAS potato and Americans waxing poetic about foreigners not being able to TP-stall recover an airliner like they're reliving their USAF UPT glory days. The quoted above is the real issue, and what needs to be talked about more. Boeing wanted to get away with not incurring certification costs of a new type by frankensteining the 73 certificate. It is therefore poetic justice they would get bent over questions of a sub-system allowed in under the very certification-stretching they've been mining for decades in the first place. About time their cost-cutting and 737 back alley plastic surgery clinic was finally exposed.
They got Capone under the lesser tax evasion, so frankly I couldn't care less whether the foreign case studies were 100% MCAS/sensor related or not. Win's a win. This ought to effectively wash out their gains in choosing to not design the "composite 757", to include accepting the certification costs a clean sheet design would normally incur.