Boeing has flown test flights of its 737 MAX to evaluate a fix for the system targeted as a potential cause of the crashes. The aviation giant, which has been under fire and has seen its flagship narrow-body planes grounded since 13 March, tested the system upgrade on Monday, two days after pilots from American and Southwest Airlines did simulation flights in Renton, Washington, the sources said. Boeing needs authorisation from the Federal Aviation Administration (FAA) before the MAX can return to service. But the company still has not submitted its proposed software patch to the FAA, a government source said.
The aircraft was grounded following two deadly accidents involving Ethiopian Airlines earlier this month and Lion Air in October that together killed 346 people. A Senate Commerce Committee panel will hold a hearing Wednesday to question FAA Acting Administration Daniel Elwell and Transportation Department Inspector General Calvin Scovel. The session is set to be followed by a second hearing at a later date with Boeing, airline pilots and other stakeholders.
The officials are expected to face questions from lawmakers on the FAA’s certification of the 737 MAX – and whether regulators have become too cosy with the company and fast-tracked some approvals.
Engineers have been focusing on problems with the Manoeuvring Characteristics Augmentation System (MCAS), a stall prevention system designed to point the nose of the 737 MAX 8 downward if it is in danger of stalling, or losing lift. The system has been criticised since it can malfunction and make it difficult for pilots to control the aircraft. Both of the recent crashes occurred moments after take-off.