The pilots of Lion Air Flight 610 requested permission to return to the Jakarta airport shortly after takeoff, but did not turn back before the plane entered a sudden dive and plunged into the Java Sea at speeds of as much as 600 miles per hour.
Indonesian accident investigators said an airspeed indicator of a Boeing Co 737 MAX plane that crashed last week was damaged for its last four flights, but U.S. authorities responded cautiously to suggestions of fleet-wide checks.
The Federal Aviation Administration (FAA) of the United States has issued an Emergency Airworthiness Directive for the Boeing 737 MAX 8 and MAX 9 aircraft types, effective immediately.
The angle of attack readings are fed into a computer that in some cases will attempt to push down the nose using the pitch trim system.
Indonesia's search and rescue agency said they are still working to locate the cockpit voice recorder which they believe is amongst the other wreckage under the sea. A separate procedure involving a specific sequence of actions can be used to disengage the sensor from feeding information to the plane's computer system to address the issue for the duration of a flight.
In that incident the plane had experienced airspeed indicator malfunctions on its four previous flights, data from the retrieved black box has revealed.
The Directorate General of Civil Aviation (DGCA) has asked Jet Airways and SpiceJet to take corrective measures to address any possible issues with their Boeing 737 Max aircraft that could lead to significant altitude loss.
Lion Air flight JT610 was en route to Pangkal Pinang, Indonesia, when it suddenly lost contact with traffic control operators after departing from Jakarta.
The angle-of-attack sensor is meant to measure the angle between air flow and a reference line on the frame or wings so that they maintain lift.
Boeing warned airlines about the features of the aircraft.
The glitch had been repeatedly serviced and Lion Air's technical team declared the plane to be airworthy.
If there is an "uncommanded nose-down stabilizer trim" on the Max, pilots can counteract it by pushing a switch on their control yoke.
KNKT said that there was a problem with the sensor on the last flight taken by the doomed plane, from the island of Bali to Jakarta, even though one sensor had been replaced in Bali. If pilots aren't careful, they can cause severe nose-down trim settings that make it impossible to level a plane.