[SystemSafety] "FAA chief '100% confident' of 737 MAX safety as flights to resume"

[Dewi Daniels]

Olwen,

Given that inability of the elevator to raise the nose or prevent it going
down is the most important symptom of the stall, I fail to see what
relevance reduced elevator authority at or near the stall has to the 737
MAX accidents. The 737 MAX accidents happened because MCAS applied full
nose-down trim, resulting in the aircraft diving and accelerating until the
control forces were so high that the pilots were unable to recover level
flight.

Yours,

Dewi Daniels | Director | Software Safety Limited

Telephone +44 7968 837742 | Email d <ddaniels at verocel.com>
ewi.daniels at software-safety.com

Software Safety Limited is a company registered in England and Wales.
Company number: 9390590. Registered office: Fairfield, 30F Bratton Road,
West Ashton, Trowbridge, United Kingdom BA14 6AZ


On Thu, 3 Dec 2020 at 13:58, Olwen Morgan <olwen at phaedsys.com> wrote:

>
> On 03/12/2020 12:43, Dewi Daniels wrote:
> >
> >
> > That isn't what is meant by a deep stall. A deep stall is one in which
> > the elevators have no authority,
>
>
> If the aircraft is in a condition where there is much reduced force on
> the column due (presumably) to much reduced aerodynamic pressure on the
> HS and elevators, does this not constitute, if not loss of authority,
> then at least much reduced authority?
>
> Once again, I'm trying to get at what kind of flight physics is going on
> with the 737 MAX airframe.
>
>
> olwen
>
>
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