A senior US politician has told the boss of Boeing: “I would walk before I would get on a 737 Max.”

Senator Jon Tester, a Democrat from Montana, was speaking at a marathon session of the Senate Commerce Committee in Washington DC.

The senators were questioning Dennis Muilenburg, president and chief executive of Boeing, about the crashes of the 737 Max that killed a total of 346 people.

The hearing took place a year to the day after Lion Air flight 610 crashed shortly after take-off from Jakarta airport. All 189 passengers and crew died when the almost-new Boeing 737 Max plunged into the Java Sea at 415mph.

The accident happened after a faulty sensor triggered an anti-stall system known as MCAS. The software forced the nose of the aircraft down despite the efforts of the pilots to override it.

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In March 2019, an Ethiopian Airlines Boeing 737 Max suffered a similar fate, in a crash that claimed 157 lives.

Shortly afterwards the Max was grounded worldwide. The aircraft remains out of service.

Boeing expects the 737 Max to be airborne again before the end of the year.

But Senator Tester said he would never fly on the plane, repeating: “I would walk. You shouldn’t be cutting corners.”

Mr Muilenburg did not respond directly – a pattern that he followed for much of the two-hour session.

Many relatives of the victims of the crashes were sitting behind the Boeing boss.

He began the session by saying to them: “I wanted to let you know, on behalf of myself and all of the men and women of Boeing, how deeply sorry I am.

“As we observe today the solemn anniversary of the loss of Lion Air flight 610, please know that we carry the memory of these accidents, and of your loved ones, with us every day.

“They will never be forgotten, and these tragedies will continue to drive us to do everything we can to make our airplanes and our industry safer.”

After his opening statement, Mr Muilenburg faced a barrage of criticism.

Tammy Duckworth, a former Army helicopter pilot and now Democrat senator for Illinois, said: “Pilots know that catastrophes don’t happen in a vacuum.

“You didn’t tell the pilots that MCAS was in there. Then you added an extra step that would trigger it again five seconds later.

“Time and again, Boeing has not told the whole truth. And these families are suffering because of this.”

The planemaker was also accused of “actively lobbying the FAA [Federal Aviation Administration] to keep planes in the air” after the second Boeing 737 Max aircraft.

Senator Jacky Rosen, a Democrat from Nevada, criticised the fact that the Boeing 737 is “still working off the same certification as 1967”, the year when the original twin-jet first flew.

“It’s almost as though you took a canoe and turned it into a cruise ship.”

Mr Muilenburg said earlier: “We know we made mistakes and got some things wrong. We own that, and we are fixing them.