FAA order pilot procedure change for Boeing 737 MAX after Lion Air

A Lion
Air Boeing 737 MAX 9.
AP

• The US Government has issued an emergency airworthiness
  directive for airlines operating the Boeing 737 MAX 8 and Boeing 737 MAX 9
  airliners. 
• The FAA directive comes one day after Boeing
  issued a safety bulletin alerting airlines
  that erroneous readings from one of the plane’s sensors
  can cause the aircraft to enter into a sudden dive.
• The directive orders airlines to update its procedures
  so pilots are properly instructed on how to react when the
  faulty sensors cause the plane to dive.
• The Indonesian government believes this condition may
  have caused Lion Air JT610 to crash in October. 

The US Federal Aviation Administration
issued an emergency airworthiness directive on Wednesday for
airlines flying the Boeing 737 MAX 8 and 737 MAX 9
airliners. 

The FAA’s emergency AD reinforces the safety warning Boeing released
on Tuesday.  Boeing’s operations manual
bulletin that advises airlines on procedures when
erroneous readings from one of the plane’s sensors lead the
aircraft to enter into a sudden dive.

According to the Indonesian National Transportation Safety
Committee, these erroneous AOA sensor readings may have triggered
an abrupt dive that brought down Lion Air Flight JT610 in
October.

“This emergency AD was prompted by analysis performed by
the manufacturer showing that if an erroneously high single angle
of attack (AOA) sensor input is received by the flight control
system, there is a potential for repeated nose-down trim commands
of the horizontal stabilizer,” The FAA said in the
directive.

“This condition, if not addressed, could cause the flight
crew to have difficulty controlling the airplane, and lead to
excessive nose-down attitude, significant altitude loss, and
possible impact with terrain.”

Read More: The Lion Air Flight 610 crash is
the worst airliner accident of 2018

In addition, the agency found that potentially deadly flaw
may manifest itself again in other Boeing 737 MAX
aircraft.

As a result, the FAA has ordered airlines to revise its
flight manuals to provide pilots with specific procedures on how
to react when these conditions occur.

Airlines are required to make the changes prescribed by the
FAA within three days of the receipt of the directive.

Lion Air Flight 610 crashed in the Java Sea shortly after taking
off from Jakarta, Indonesia, on October 28. All 189 people on
board the flight were killed. Flight JT610 marked the first fatal
crash involving Boeing’s next-generation 737 Max aircraft.

The 737 Max, the fastest-selling plane in Boeing history, is the
latest version of the company’s 737-family of jets. Boeing has
more than 4,500 unfilled orders for the 737 Max on its books.

Here’s the directive in its entirety: