BA Boeing Co

By Robert Wall and Ben Otto 

A senior Boeing Co. executive defended the company's aircraft design and production processes following two fatal crashes of its 737 MAX airliner, and said fixes to software linked to at least one of those crashes should be ready within weeks.

Boeing's commercial plane marketing vice president, Randy Tinseth, said he had "great confidence" in the 737 MAX and the process by which Boeing devised the plane.

"I know the discipline and rigor of our design process. I know the integrity of our production process," he said at an investors briefing in London.

U.S. officials, including the Justice Department and the Department of Transportation's inspector-general office, are scrutinizing steps taken by Boeing and the U.S. Federal Aviation Administration, the plane maker's principal regulator, to get the MAX into service. Congress also has scheduled hearings.

These officials started looking at the plane's design process after a Lion Air-operated 737 MAX crashed in Indonesia in October, killing 189 people. Investigators are focusing on the MAX's stall-prevention system as having potentially played a role in the crashes. Boeing has promised to roll out a software fix for the system. Mr. Tinseth said Thursday that Boeing expected that fix to be approved by U.S. regulators in weeks.

After another MAX, operated by Ethiopian Airlines, crashed in March killing 157 people, aviation authorities around the world cited similarities between the two crashes and grounded the jetliner. The investigation into the Ethiopian Airlines crash has just begun.

Mr. Tinseth said modifications are planned to both software and training.

"That includes changes in the control laws of the airplane, an update of the displays, the flight manual as well as the training. We are working closely with the (Federal Aviation Administration) on that," he said.

Accident investigators have said the Lion Air plane suffered erroneous sensor information that caused the stall-prevention system to misfire, repeatedly pushing the nose of the plane down during the 11-minute flight before all contact was lost. They have also said they are looking at maintenance and cockpit-crew responses.

Crew flying the same MAX aircraft on a prior flight also experienced the flight-control malfunction. Pilots overcame the problem by flying manually, investigators said previously. On Thursday, they added that the plane was also flying with a third pilot in the cockpit who was qualified to fly the MAX, and who was hitching a ride while off-duty.

The investigators also said the final accident report for the Lion Air crash will likely be issued in August or September.

A senior Ethiopian aviation official on Wednesday told The Wall Street Journal the country had fast-tracked its probe and was hoping to issue a preliminary report next week. U.S. air-safety experts and Boeing have supported both investigations.

Nurcahyo Utomo, an air-crash investigator with Indonesia's National Transportation Safety Committee, said Thursday that the Lion Air jet's cockpit voice recorder -- one of two black boxes recovered from the jet's crash site on the ocean floor -- revealed that the two pilots of the final flight were calm at first, then seemed to panic when it became clear they couldn't recover. He declined to go into detail. The flight hit the water at high speed, causing the plane to disintegrate.

Write to Robert Wall at robert.wall@wsj.com and Ben Otto at ben.otto@wsj.com

(END) Dow Jones Newswires

March 21, 2019 14:10 ET (18:10 GMT)

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