Senate panel grills Boeing CEO over flaws in MAX jet

At a heated Senate hearing Tuesday, Boeing CEO Dennis Muilenburg said the grounded 737 MAX jet will fly again only when "everyone is convinced it's safe".

Muilenburg was questioned by the US Senate Committee on Commerce, Science and Transportation in Washington over what the company knew about its MCAS stall-prevention system linked to two deadly plane crashes and about delays in turning over internal 2016 messages that described erratic behavior of the software in a simulator.

The hearing put pressure on a revamped Boeing senior management team fighting to repair trust with airline customers and passengers shaken by an eight-month safety ban on its 737 MAX following the crashes. The crashes on Oct 29, 2018, in Indonesia and March 30 in Ethiopia killed 346 people.

"This is not going to be timeline driven," Muilenburg testified. "We are committed to answering every question regulators have."

Investigators have focused on the jet's anti-stall device, called the Maneuvering Characteristics Augmentation System (MCAS), which may have erroneously pointed the nose of the planes down to gain speed to prevent a mid-air stall, and into a fatal plunge.

"You have told me half-truths over and over again," Senator Tammy Duckworth of Illinois told Muilenburg, questioning why the manufacturer did not disclose more details about MCAS' lack of safeguards. "You have not told us the whole truth and these families are suffering because of it."