The hearing on federal oversight on commercial aviation by the Senate commerce subcommittee on aviation and space will include the US Federal Aviation Administration's (FAA) acting administrator Dan Elwell, National Transportation Safety Board chairman Robert Sumwalt and transportation department inspector general Calvin Scovel. It is meant to prevent a loss of lift which can cause an aerodynamic stall and send the plane downwards in an uncontrolled way.
Facing such high-profile scrutiny, Boeing, one of the United States' most prestigious exporters, reshuffled executives in its commercial airplanes unit to focus on the crash fallout.
A crew that flew the same plane the evening before had the same problem with the plane's nose.
In the case of the Lion Air crash in Indonesia, it has raised questions about whether crew used the correct procedures.
A source told Reuters that someone mentioned the plane's airspeed on the cockpit voice recording, and a second source said one of the plane's indicators showed a problem on the captain's display but not the first officer's.
Cockpit Voice Recorder (CVR) of a Lion Air JT610 that crashed into Tanjung Karawang sea is seen inside a special container after it was found under the sea, during a press conference at Tanjung Priok Port in Jakarta, Indonesia, January 14, 2019.
Among them: how new automated features of the plane were "tested, certified, and integrated"; what safety assumptions "led to the FAA's decision not to revise pilot training programs and manuals" to reflect the automated features; how the FAA's delegation of authority to Boeing may have affected the certification process; and what corrective actions have been taken since the initial accident in October 2018. The data was back in Addis Ababa on Tuesday, sources familiar with the probe told Reuters.
ULET IFANSASTI GETTYWheels from the crashed Lion Air flight JT 610
The next day, a different crew aboard the doomed aircraft faced what investigators said was the same malfunction and plunged into the Java Sea.
"We can't provide additional comment at this stage due the ongoing investigation on the accident", Lion Air spokesman Danang Prihantoro said by phone.
Boeing Company, the world's biggest planemaker, faces growing obstacles to returning its grounded 737 Max fleet to the skies, while details emerged of potential similarities between the two crashes. They're also checking if the pilots were trained about the system. The FAA is part of the U.S. Department of Transportation.
For now, more than 350 MAX aircraft are grounded, and deliveries of almost 5,000 more - worth more than $500 billion - are on hold.
The MAX, which offers cost savings of about 15 per cent on fuel, was developed for service from 2017 after the successful launch by its main rival of the Airbus A320neo.
It is so far unclear whether Beijing is going to replace the 737 MAX with other planes produced by Boeing.