Boeing to update 737 software

More countries join in grounding jet model, US politicians call on FAA to follow suit

Boeing said it will make a major software change to its 737 MAX 8 aircraft flight-control system as more countries on Tuesday grounded the jets following the crash of one in Ethiopia.

The new software for the MAX 8 will enable the plane's stall-prevention system to use multiple data feeds rather than relying on the single sensor employed when the plane was delivered in 2017, Boeing said.

Boeing's software change follows preliminary results from the crash of a MAX 8 in Indonesia last October, suggesting that bad data from a single sensor, which measures the angle of the plane's nose, caused the stall-prevention system to malfunction, perhaps sending the 737 MAX 8 into the dive that killed 189 people.

The company said it developed the software change prior to Sunday's crash of the Ethiopian Airlines plane that killed all 157 people aboard. The software update will make an "already safe plane safer", the company said late Monday.

On Tuesday, the European Aviation Safety Agency and the governments of the United Kingdom, Ireland, France and Germany barred 737 MAX 8 jets from their airspace. Australia, India and Singapore also grounded the MAX 8, as did Norwegian Airlines.

Only two nations still fly a substantial number of Boeing 737 MAX 8s: the United States and Canada. US airlines Southwest has 34 and American 24. Both have said they have analyzed data from their thousands of flights with the planes and found no reason to ground them. Air Canada, which operates 24 Max 8s, has given no indication it intends to ground them.

The US Federal Aviation Administration (FAA) said it was sticking with its refusal to ground the jet model.

"It's too soon to declare the plane unsafe to fly," the FAA said in a statement. "This investigation has just begun and to date we have not been provided data to draw any conclusions or take any actions."

"The FAA should sit up and take notice in view of the European Aviation Safety Agency's decision to bar the plane from European airspace,'' Scott Hamilton, managing director of Leeham Co, an aviation consultancy firm in Seattle, told China Daily.

The cause of the Indonesian and Ethiopian crashes is unknown, but both planes appeared to have had trouble with their stall prevention system, he said. "This warrants grounding the plane until the cause of the crashes is known."

Hamilton said he was puzzled by Boeing's decision to use a single sensor in the MAX 8's stall prevention system.

"Redundancy is one of the basic philosophies of aviation so you don't have a single point of failure," he said. "You want back-up."

"The FAA is between a rock and a hard place," said Keith Mackey, an aviation safety consultant and president of Mackey International in Ocala, Florida. "The FAA has certified the plane. Until investigators come up with something definitive making the plane un-airworthy, there's no reason to ground it. I think the recorders should tell a good portion of the story."

American politicians on Tuesday demanded immediate grounding of the aircraft, and Boeing's stock was down on Tuesday for the second day. It closed on the New York Stock Exchange at $375.41 a share, down $24.60, or 6.15 percent from Monday's close. Boeing's stock has lost about $20 billion in two days.

Senator Elizabeth Warren of Massachusetts, who is seeking the Democratic presidential nomination, said, "The FAA needs to get these planes out of the sky." She called for congressional hearings on "whether an administration that famously refused to stand up to Saudi Arabia to protect Boeing arms sales has once again put lives at risk for the same reason."

Senator Mitt Romney, a Republican from Utah, joined Democratic Senators Richard Blumenthal from Connecticut and Diane Feinstein from California, in demanding the grounding of the aircraft.

The Transport Workers Union of American, representing about 150,000 aircraft mechanics, baggage handlers and flight attendants, said the Boeing MAX 8 planes should be grounded "in an abundance of caution".

Boeing CEO Dennis A. Muilenburg spoke to US President Donald Trump on the phone Tuesday morning and argued that the MAX 8 shouldn't be grounded in the United States, according to two people briefed on the conversation, The New York Times reported. A Boeing official said that during the call, "Dennis reiterated our position that the Max is a safe aircraft," according to the newspaper.

Nearly 40 percent of the in-service fleet of 371 Boeing 737 MAX 8 jets globally has been grounded, according to industry publication Flightglobal. Earlier, China, Malaysia and Oman had ordered the aircraft grounded.

China, Boeing's biggest market for its MAX 8, has grounded 96 jets. The USA is the second largest MAX 8 market, with 72 aircraft in service, Flightglobal reported.

US regulators are expected to require installation of Boeing's new software, which takes about an hour per airplane, by the end of April.

AP contributed to this story.