FAA issues MAX 8 and MAX 9 emergency airworthiness directive
On Wednesday, the U.S. Federal Aviation Administration (FAA) issued an emergency airworthiness directive to owners and operators of Boeing B737 MAX 8 and MAX 9 aircraft, following a fatal crash of a Lion Air MAX 8 in Indonesia last week which killed all 189 passengers and crew onboard. Read More »
The emergency ruling 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. 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”, the FAA said.
The directive requires MAX owners and operators to revise the operating procedures of the airplane flight manual (AFM) to provide the flight crew with runaway horizontal stabilizer trim procedures to follow under certain conditions.
The FAA order was based on preliminary findings from the Indonesian investigation into the October 29 crash of a Lion Air MAX 8 off the coast of Java. FAA directives are usually followed by other airline regulators internationally.
The MAX 8, PK-LQP, departed Jakarta’s main airport on a short routine flight to Pangkal Pinang, a tin mining hub. Shortly after take-off, the captain requested a return to base for unknown reasons. The plane did not make it to Jakarta. It vanished from radar 13 minutes after take-off.
Flightradar24 data suggested the aircraft had difficulty maintaining level flight. It ascended to 2,500ft, then dropped, climbed again and finally fell from the sky. The same plane had experienced a technical issue on its previous flight from Denpasar to Jakarta. It has been speculated that the cockpit crew received incorrect airspeed readings, possibly from clogged or otherwise malfunctioning pitot tubes.
The flight data recorder has been recovered and the search for the cockpit voice recorder was continuing at press time.
Indonesian transport minister, Budi Karya Sumadi, has ordered the temporary suspension of Lion Air technical director, Muhammad Asif. The airline has named Muhammad Rusli as its acting technical director until further notice. The Ministry of Transportation also ordered Lion Air to suspend the engineers who cleared the jet to fly.
Boeing and the U.S. National Transportation Safety Board are supporting the investigation. It is the first time a B737 MAX has crashed. The jet was on lease to Lion Air from China Minsheng Financial Leasing.
The crash is the second worst in Indonesian aviation history. In 1997, a Garuda Indonesia A300 crashed in Medan. The third worst accident was the Indonesia AirAsia A320 crash in late December 2014. Lion Air has had 11 major accidents since 2002, including the loss of five aircraft.