Acting FAA Administrator Daniel Elwell testifies at a congressional hearing. (House Transportation and Infrastructure Committee via YouTube)

The acting head of the Federal Aviation Administration acknowledged during a congressional hearing today that his agency will tighten up its regulatory procedures as a result of the investigation into two fatal crashes of Boeing 737 MAX jets.

Acting Administrator Daniel Elwell said he was concerned to hear that Boeing waited more than a year before informing the FAA that a cockpit indicator known as the AOA Disagree alert didn’t work as designed, due to a software gap. The agency was told about the gap only after a Lion Air 737 MAX crashed in Indonesia last October, killing all 189 people on board.

“I’m concerned that it took a year, and we’re looking into that, and we’re going to fix that,” Elwell, a former airline pilot, told Rep. Peter DeFazio, D-Ore., during a hearing before the House Aviation Subcommittee. “It shouldn’t take a year for us to find out that that discovery was made.”

Elwell said the FAA agreed with Boeing at the time that the alert was not a safety-critical feature, and could be fixed during a future software update.

But then a second plane crashed in Ethiopia in March, killing another 157 people and leading the FAA and other regulatory agencies to ground all 737 MAX jets. Investigations tentatively traced both crashes to bad data from an angle-of-attack sensor. In each case, spurious data apparently caused an automatic flight control system known as the Maneuvering Characteristics Augmentation System, or MCAS, to push the plane into a catastrophic dive.

It’s debatable whether one or both of the crashes could have been averted if the AOA Disagree alert worked as designed. Boeing says the alert will be activated as a standard feature once 737 MAX planes return to flight.

Some airline pilots have complained about not having enough information about the MCAS system and its potential pitfalls, and in response to questioning, Elwell acknowledged that “the MCAS should have been more adequately explained in the ops manual and the flight manual, absolutely.”

However, Elwell emphasized that the crashes were the result of a chain of events that also included pilot actions, or inactions. In the Indonesia case, the pilots apparently didn’t follow the specified procedures for counteracting problems with the plane’s stabilizer trim. In the Ethiopia case, the pilots did try the procedures, but apparently maintained an airspeed so high that they couldn’t wrest back control of the plane.

“I’ve never looked at an accident where there weren’t three or four or five links of the chain, any one of which, if it hadn’t gone wrong, the plane would have survived,” he said.

Boeing and the FAA are facing multiple investigations focusing not only on the crashes, but also on the process by which the 737 MAX was certified for flight.

One of the issues has to do with how the FAA delegates responsibilities for certification testing to airplane manufacturers. Some reports have suggested that Boeing took on too much responsibility for analyzing the effects of the MCAS system. But Elwell has said that without the cooperative approach to safety analysis, the FAA would need 10,000 more employees and $1.8 billion in additional funding.

During today’s hearing, Subcommittee Chairman Rick Larsen, D-Wash., asked Elwell whether the FAA had considered going back to an earlier arrangement that gave regulators more direct oversight over Boeing’s representatives. In response, Elwell noted that the process was still the subject of investigation and review.

“At this point, to say that we’re willing to go back to something before we’ve gone through those investigations, I’m not prepared to say that,” he said. “I really want to see what these investigations and these audits have to say about our current system.”

Elwell noted that the FAA is still working with Boeing to certify a software update that’s meant to upgrade the MCAS and build in additional safeguards. The FAA is due to convene a meeting with its counterparts around the world on May 23 to discuss the 737 MAX and potentially consider a timeline for returning the planes to service by late summer.

The global grounding of the 737 MAX is said to be costing airlines hundreds of millions of dollars, and newly manufactured planes are stacking up at Boeing’s assembly plant in Renton, Wash. This week Boeing acknowledged that factory-fresh 737 MAX planes are being sent to a San Antonio facility for storage.

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