Boeing has not handed over key documents in Alaska Airlines door plug probe: NTSB chair

Boeing has not fully cooperated with the National Transportation Safety Board's investigation into the Alaska Airlines door plug incident, NTSB Chair Jennifer Homendy said during a Senate hearing on Wednesday.

"Boeing has not provided us with the documents and information that we have requested numerous times over the past few months, specifically with respect to opening, closing and removal of the door and the team that does work at the Renton facility,” Homendy said during a Senate Commerce Committee hearing.

Homendy said a team of 25 people at a company facility in Renton, Washington, deals with the doors. She said the manager of the team has been on medical leave, and the NTSB have not been able to interview the manager. Despite asking for the names of the 25 people on the team, Boeing has refused to give that information to the NTSB, Homendy said.

"It's absurd that two months later, we don't have that," Homendy said and noted that the NTSB has engaged their attorney on this matter.

Boeing said in a statement to ABC News that the company has "worked proactively and transparently" to support the NTSB's investigation, including by responding "comprehensively" to all agency requests with relevant information.

"Early in the investigation, we provided the NTSB with names of Boeing employees, including door specialists, who we believed would have relevant information. We have now provided the full list of individuals on the 737 door team, in response to a recent request," the statement said. "With respect to documentation, if the door plug removal was undocumented there would be no documentation to share."

"We will continue to cooperate fully and transparently with the NTSB’s investigation," the company said.

Sen. Maria Cantwell, D-Wash., asked Homendy on Wednesday if the fact that Boeing had not produced the documents meant that the company wasn't able to retrieve them or if it meant they didn't exist.

"They may not," said Homendy. "There are two options. Either they exist and we don't have them, or they do not exist, which raises two very different questions -- several different questions, depending on which one is the right answer."

Homendy said the NTSB was informed that Boeing has a procedure to maintain documents when work on door plugs is performed, but the NTSB has not been able to verify that.

The door plug fell off a few minutes after Alaska Flight 1282 took off from Portland International Airport on Jan. 5. Passengers captured footage showing a hole where the door plug came loose on the Boeing 737 Max 9 plane. The plane safely made an emergency landing and no one was seriously injured.

The Federal Aviation Administration grounded approximately 171 Max 9s worldwide following the incident. Alaska Airlines resumed flying the Boeing 737 Max 9 following fleet inspections on Jan. 26.

An NTSB preliminary report released last month found that four bolts designed to prevent the door plug from falling off the Boeing 737 Max 9 plane were missing before the plug blew off the flight.

Boeing said it would review the NTSB's findings "expeditiously" in a statement following the release of the report.

"Whatever final conclusions are reached, Boeing is accountable for what happened. An event like this must not happen on an airplane that leaves our factory," Boeing president and CEO Dave Calhoun said in a statement in February. "We simply must do better for our customers and their passengers."

The Federal Aviation Administration is increasing its oversight of Boeing and began an audit of the company's production and manufacturing in the wake of the door plug blow-out.

The Justice Department is also investigating the Alaska Airlines incident, three sources familiar with the situation told ABC News.

The probe will also examine specifically whether Boeing violated its 2021 deferred prosecution agreement when the company was investigated by the Justice Department over two 737 Max crashes. The deferred prosecution agreement forced Boeing to cooperate with federal government probes and fined the company $2.5 billion after Lion Air Flight 610 and Ethiopian Airlines Flight 302, both 737 Max planes, crashed.