Trump grounds troubled 737 MAX aircraft, Boeing stock tumbles
US
President Donald Trump has decided to ground all Boeing 737 Max
airplanes, citing safety concerns after the fatal crash in Ethiopia.
The US was among the last holdovers in grounding the controversial
jet.
“The
safety of the American people and all people is our paramount
concern,” Trump said Wednesday at the White House, announcing the
measure. The order applies to all Max 8 and Max 9 versions of the
popular airliner.
Planes
that are in the air will be grounded...upon landing at the
destination.
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Boeing, The FAA, And Why Two 737 MAX Planes Crashed
12
March, 2019
On
Sunday an Ethiopian Airlines flight crashed, killing all on board.
Five month earlier an Indonesian Lion Air jet crashed near Jakarta.
All crew and passengers died. Both airplanes were Boeing 737-8 MAX.
Both incidents happened shortly after take off.
Boeing
737 MAX aircraft are now grounded about
everywhere except
in the United States. That this move follows only now is sad. After
the first crash it was already obvious that the plane is not safe to
fly.
The
Boeing 737 and the Airbus 320 types are single aisle planes with some
150 seats. Both are bread and butter planes sold by the hundreds with
a good profit. In 2010 Airbus decided to offer its A-320 with a New
Engine Option (NEO) which uses less fuel. To counter the Airbus move
Boeing had to follow up. The 737 would also get new engines for a
more efficient flight and longer range. The new engines on the 737
MAX are bigger and needed to be placed a bit different than on the
older version. That again changed the flight characteristics of the
plane by giving it a nose up attitude.
The
new flight characteristic of the 737 MAX would have require a
retraining of the pilots. But Boeing's marketing people
had told their
customers all along that the 737 MAX would not require extensive new
training. Instead of expensive simulator training for the new type
experienced 737 pilots would only have to read some documentation
about the changes between the old and the new versions.
To
make that viable Boeing's engineers had to use a little trick. They
added a 'maneuver characteristics augmentation system' (MCAS) that
pitches the nose of the plane down if a sensor detects a too high
angle of attack (AoA) that might lead to a stall. That made the
flight characteristic of the new 737 version similar to the old one.
But
the engineers screwed up.
The
737 MAX has two flight control computers. Each is connected to only
one of the two angle of attack sensors. During a flight only one of
two computer runs the MCAS control. If it detects a too high angle of
attack it trims the horizontal stabilizer down for some 10 seconds.
It then waits for 5 seconds and reads the sensor again. If the sensor
continues to show a too high angle of attack it again trims the
stabilizer to pitch the plane's nose done.
MCSA
is independent of the autopilot. It is even active in manual flight.
There is a procedure to deactivate it but it takes some time.
One
of the angle of attack sensors on the Indonesian flight was faulty.
Unfortunately it was the one connected to the computer that ran the
MCAS on that flight. Shortly after take off the sensor signaled a too
high angle of attack even as the plane was flying in a normal climb.
The MCAS engaged and put the planes nose down. The pilots reacted by
disabling the autopilot and pulling the control stick back. The MCAS
engaged again pitching the plane further down. The pilots again
pulled the stick. This happened some 12 times in a row before the
plane crashed into the sea.
To
implement a security relevant automatism that depends on only one
sensor is extremely bad design. To have a flight control automatism
engaged even when the pilot flies manually is also a bad choice. But
the real criminality was that Boeing hid the feature.
Neither
the airlines that bought the planes nor the pilots who flew it were
told about MCAS. They did not know that it exists. They were not
aware of an automatic system that controlled the stabilizer even when
the autopilot was off. They had no idea how it could be deactivated.
Nine
days after the Indonesian Lion Air Flight 610 ended in a deadly
crash, the Federal Aviation Administration (FAA) issued an
Emergency Airworthiness Directive.
“This is the first description you, as 737 pilots, have seen. It is not in the AA 737 Flight Manual Part 2, nor is there a description in the Boeing FCOM (flight crew operations manual),” says the letter from the pilots’ union safety committee. “Awareness is the key with all safety issues.”
The
Ethiopian Airlines plane that crashed went down in a similar flight
profile as the Indonesian plane. It is highly likely that MCAS is the
cause of both incidents. While the pilots of the Ethiopian plane were
aware of the MCAS system they might have had too little time to turn
it off. The flight recorders have been recovered and will tell the
full story.
Boeing
has sold nearly 5,000 of the 737 MAX. So far some 380 have been
delivered. Most of these are now grounded. Some family members of
people who died on the Indonesian flight are suing Boeing. Others
will follow. But Boeing is not the only one who is at fault.
The
FAA certifies all new planes and their documentation. I was for some
time marginally involved in Airbus certification issues. It is an
extremely detailed process that has to be followed by the letter.
Hundreds of people are full time engaged for years to certify a
modern jet. Every tiny screw and even the smallest design details of
the hardware and software have to be documented and certified.
How
or why did the FAA agree to accept the 737 MAX with the badly
designed MCAS? How could the FAA allow that MCAS was left out of the
documentation? What steps were taken after the Indonesian flight
crashed into the sea?
Up
to now the FAA was a highly regarded certification agency. Other
countries followed its judgment and accepted the certifications the
FAA issued. That most of the world now grounded the 737 MAX while it
still flies in the States is a sign that this view is changing. The
FAA's certifications of Boeing airplanes are now in doubt.
Today
Boeing's share price dropped some 7.5%. I doubt that it is enough to
reflect the liability issues at hand. Every airline that now had to
ground its planes will ask for compensation. More than 330 people
died and their families deserve redress. Orders for 737 MAX will be
canceled as passengers will avoid that type.
Boeing
will fix the MCAS problem by using more sensors or by otherwise
changing the procedures. But the bigger issue for the U.S. aircraft
industry might be the damage done to the FAA's reputation. If the FAA
is internationally seen as a lobbying agency for the U.S. airline
industry it will no longer be trusted and the industry will suffer
from it. It will have to run future certification processes through a
jungle of foreign agencies.
Congress
should take up the FAA issue and ask why it failed.
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