AOPA Turbine Pilot Magazine - March 2020 - T-2

TURBINE PILOT

FROM THE EDITOR

MAX fallout
Pushed to the limit
HERE WE ARE FACING MARCH, the time when
Boeing said in the fall that its controversial
737 MAX would re-enter service. Think it
will happen? The airplane has drawn plenty
of criticism since two 737 MAX crashes killed
346 passengers, and an investigation revealed
that its stall-protection system had fatal flaws.
Some airlines canceled orders for the MAX,
but Boeing kept making them-only to languish undelivered. In December, the FAA
proposed a fine of $3.4 million on Boeing for
faulty parts. Apparently many 737NGs and
737 MAXs had been fitted with slat tracks that
had been weakened by the presence of extra
hydrogen during the manufacturing process.
It goes on like this, right up to the failure of
Boeing's Starliner space capsule to dock with

BY THOMAS A. HORNE

Turbine Pilot Editor

Augmentation System (the errant stall protection system that set all this in motion),
they were shifted away from other tasks.
General aviation manufacturers encountered weeks and months of delays in
securing certification approvals for both airframes and avionics.
All because Boeing pushed the limits of
a 50-year-old airplane's design.
Engines have become more fuel-efficient in recent years, partly because of the
development of bigger fan sections. Bigger
fan sections-such as the CFM International
LEAP-1Bs used in the MAX-can't fit under
the 737's wings. The landing gear are too

Of course, none of these gyrations happened in a vacuum.
the International Space Station. Seems the
Starliner's timer was set 11 hours in error.
All this, and more, from the United
States' flagship aircraft manufacturer. What
happened? Some industry insiders trace the
trouble back to the 1996 merger of Boeing
with McDonnell-Douglas. Up to that time,
Boeing prioritized its engineering expertise.
McDonnell-Douglas was known for its focus
on the bottom line. This may have influenced the 737 MAX's design compromises.
Boeing CEO Dennis Muilenburg took
the heat for the MAX fiasco. He was fired,
but if this was punishment it was probably
softened by a departure package featuring
$62 million in equity and pension benefits,
plus $18 million in stock options. Now it's up
to a new company president to pick up the
pieces and move forward, even if that means
the cancellation of the entire MAX program.
Of course, none of these gyrations happened in a vacuum. They had repercussions.
Spirit AeroSystems, a major parts supplier
for the Boeing 737 MAX, laid off 2,800
employees when MAX production was
temporarily halted in January 2020. As the
FAA reallocated its staffers to investigate
the MAX's Maneuvering Characteristics
T-2 | AOPA PILOT March 2020

short because they retract inward and stow
in the fuselage. So, to make the new engines
fit on the MAX, they were mounted on pylons
extending ahead of the wing. Flight tests discovered that at or near stall angles of attack,
with flaps up and autopilot off, the airplane
tended to pitch up and further aggravate a
stall condition. So, the MCAS was added. Its
job was to automatically make nose-down
commands to counteract this tendency.
Boeing didn't mention the MCAS in its flight
manuals, and pilots weren't taught about it,
because Boeing believed the MCAS replicated the stall behavior of other 737 type
variants. However, as two airline crews discovered, the MCAS could, in essence, run
away and cause the airplane to enter a highspeed dive with pitch forces too high for a
human to counter them. That's the MCAS
issue in a grossly abbreviated nutshell.
Instead of pushing the MAX way beyond
the originally anticipated limits of the 737
design, Boeing should have come up with
a new airplane-one that could handle bigger engines and stand taller on the ramp. But
that would have cost a lot of money. AOPA
EMAIL tom.horne@aopa.org

AOPA Turbine Pilot Magazine - March 2020

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