The head of the Federal Aviation Administration defended his decision to wait three days after a deadly crash in Ethiopia before ordering all Boeing 737 Max jets grounded, but he refused to divulge whether President Donald Trump had asked him to do so.

Acting FAA Administrator Dennis K. Elwell faced sharp questions Wednesday from senators in both parties at a Commerce, Science and Transportation subcommittee hearing about the grounding decision and the FAA’s certification of the 737 Max planes, especially the agency’s process that allows manufacturers to self-certify compliance with safety requirements.

“These crashes and subsequent reports on how the 737 Max was approved have badly shaken consumer confidence,” Aviation and Space Subcommittee Chairman Ted Cruz said at the start of the hearing. “The questions raised about the integrity of our regulatory processes strikes right to the heart of aviation safety.”

Near the end of the hearing, the Texas Republican asked Calvin L. Scovel, the inspector general for the Department of Transportation, about a 2012 report his office prepared that showed FAA employees were being rated on how many planes were delivered.

Scovel, who said an audit of how the 737 Max was certified would take 10 months or more, said he did not know if employee incentives were being offered now. Cruz responded that concerns about them “paint a troubling picture of agency capture” by the industry it regulates.

Elwell said the FAA has “strict oversight” of companies that self-certify, and that the process for certifying the 737 Max was similar to previous planes.

He also said that if the FAA were barred from letting companies self-certify, it would need 10,000 additional federal employees, and that European regulators use the process more than the FAA does.

Scovel said his office has frequently criticized the way the FAA manages companies that have so-called organization designation authorization.

“FAA now delegates more of its aircraft certification to approved manufacturers,” Scovel said. “In 2015, we reported that its oversight was not based on risk. In response to our recommendations, FAA plans to revamp its ODA oversight process by the end of July 2019. Sustained management attention will remain essential to ensure that ODA companies comply with safety regulations.”

Use of data

The March 13 order to ground the planes, which came after other airlines and countries around the world had already done so, was based on enhanced satellite data Elwell said he received that morning.

“We may have been the last countries to ground the aircraft, but the United States and Canada were the first countries to ground the aircraft with data,” Elwell said. He said officials in other countries had called the FAA after they had issued grounding orders to find out what data the United States had, because they would need it if and when they decide to allow the planes to fly again.

The data Elwell said he received showed similarities between the March 10 crash of Ethiopian Airlines flight 302, which killed 157 people, and the Oct. 29, 2018, crash of Lion Air flight 610 in Indonesia, which killed 189. He said the agency was continuing to seek information about the crashes.

“I want to assure you and everyone else the FAA will go wherever the facts lead us in our pursuit of safety,” Elwell said in his opening statement. “The 737 Max will return to service for U.S. carriers only when the FAA’s analysis of the facts and technical data indicate that it is appropriate to do so.”

Trump announced the grounding order before the FAA issued it. In questioning by Connecticut Democratic Sen. Richard Blumenthal, Elwell said he had advised Trump and Transportation Secretary Elaine Chao about his decisions, but he refused to say if Trump had asked him to ground the planes.

In the wake of the Lion Air crash, Boeing had begun preparing a software update to a system that is designed to push the plane’s nose down if a flight angle is detected that could lead to a stall. That system is suspected in both crashes because flight paths show the planes repeatedly climbing and diving.

At an earlier hearing Wednesday on the DOT’s budget, Sen. Dianne Feinstein said she was preparing legislation to require that safety features be part of a plane’s base price. The California Democrat said she was reacting to reports that some features that might have prevented the 737 Max crashes were bundled as an upgrade by Boeing.

Asked about those reports at the later hearing, Elwell said the upgrades in question would add indicators in the cockpit about what flight angle sensors were showing, so pilots could know if a false reading is being received.

He said that if the FAA determines a feature is critical to the plane’s safety, it would not let a manufacturer sell it as an upgrade. Under questioning from Massachusetts Democratic Sen. Edward J. Markey, however, he would not say if he thought the cockpit indicators should be made mandatory.

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