Top Democrats on the House Committee on Transportation and Infrastructure want Boeing to make employees available for interviews ahead of another planned hearing into the design, development and certification of Boeing 737 Max aircraft.
The committee declined to provide a copy of the letter sent on 12 September to Boeing chief executive Dennis Muilenburg by lawmakers Peter DeFazio of Oregon and Rick Larsen of Washington. Boeing did not immediately respond to a request from Cirium affiliate FlightGlobal for more information, such as the names of the employees and whether the company intends to present them for interviews.
"It’s important to the committee’s investigation to hear from relevant Boeing employees who can provide unique insight into specific issues and decisions in a way that senior Boeing management simply cannot," the House committee says in a statement.
A spokeswoman for the committee says a hearing about 737 Max aircraft is being planned "in the coming weeks" but tells Cirium the letter "is not a request for any of these individuals to appear as witnesses at a hearing".
US lawmakers have questioned witnesses about Max aircraft during numerous hearings since the worldwide grounding of those aircraft in March following the deaths of 346 passengers and crew in two crashes. Witnesses included trade association representatives, members of pilots unions, officials from federal agencies and relatives of crash victims. Nobody has so far represented Boeing during hearings in the House or Senate.
DeFazio, who is chairman of the House transportation committee, has said Boeing delivered documents in response to the committee's investigation about potential mistakes leading up to the crashes, including information about the certification process. DeFazio's stance during hearings is that lawmakers are investigating the history of Max aircraft certification before formally requesting Boeing employees to appear as witnesses.
DeFazio and Larsen, who is chair of the House aviation subcommittee, have both expressed concerns about how the US Federal Aviation Administration (FAA) allowed Boeing to oversee parts of its own safety certification for Max aircraft. This includes concerns about whether Boeing used this opportunity to rush the process and avoid gaining a new type certification for Max aircraft.
"We must look into whether there should be a cutoff point when the number of changes requires the FAA to treat a proposed aircraft design as a new plane altogether and perform an exhaustive review, nose to tail," DeFazio said during a hearing in June.
Investigations into the crashes of Ethiopian Airlines flight 302 and Lion Air flight 610 remain ongoing, but evidence indicates that automated flight control software created by Boeing automatically trimmed the aircraft into dives after being triggered by problems with an angle-of-attack indicator. The software was designed specifically for Max aircraft to make them fly like earlier-generation 737NG aircraft.
Boeing is coordinating with the FAA on software modifications to gain approval from the regulator to return Max aircraft to service.