The chair of the House Transportation Committee has sent Boeing chief executive Dennis Muilenburg dozens of questions related to the 737 Max, including those touching on Boeing’s involvement in regulatory decisions and the information the company knew about Max risks, and when.

The chair of the House Transportation Committee has sent Boeing chief executive Dennis Muilenburg dozens of questions related to the 737 Max, including those touching on Boeing’s involvement in regulatory decisions and the information the company knew about Max risks, and when.

The questions from committee chair Peter DeFazio follow up on Muilenburg’s late October testimony to the committee about the Max.

DeFazio asks Muilenburg whether Boeing assisted the Federal Aviation Administration in creating the emergency airworthiness directive (AD) issued after the first 737 Max crash – that of a Lion Air aircraft in October 2018.

The directive, which proved insufficient to prevent a second crash, did not specifically mention the aircraft’s Maneuvering Characteristics Augmentation System (MCAS), DeFazio notes.

At that point, little was known about MCAS, either by airlines or pilots. New to the Max, MCAS pushes the aircraft’s nose down, and its erroneous activation on both crashed aircraft preceded the two disasters.

“Did Boeing have any discussions with the FAA, written or oral, specifically about whether MCAS should be mentioned in this document?” DeFazio asks Muilenburg, according to a summary of questions released by DeFazio’s office.

Boeing did not immediately respond to a request for comment from FlightGlobal.

DeFazio also asks Muilenburg to specify what information the company learned about the MCAS risk after the first crash, and what it learned after the second. The second aircraft, an Ethiopian Airlines Max, went down in March.

Additionally, DeFazio questions why Boeing “made clear it believed” a grounding was unnecessary even after the second crash. He asks whether Muilenburg agreed with the decision, made by regulators globally, to ground the aircraft.

“If Boeing felt that the 737 Max was safe enough to not warrant grounding, why was it then pursuing software changes to MCAS even before the Ethiopian Airlines crash?” DeFazio asks.

He enquires whether Muilenburg still believes pilots should not need MCAS-specific training.

Boeing has said it did not make MCAS known to pilots because the system’s failure would present as a runaway stabiliser – an event to which pilots should already be to trained to address.

“Do you now believe that pilots should have known about MCAS before flying the Max?” DeFazio asks.

He is seeking answers on how much Boeing knew about the “catastrophic risk” posed by a faulty angle-of-attack (AOA) sensor on the Max. A faulty AOA triggered MCAS on both aircraft, sending them into dives from which the pilots did not recover, according to accident investigators.

DeFazio’s questions also address broader topics, such as steps Boeing has taken to address the types of issues found on the Max and the 787, which was temporarily grounded due to battery problems, and when Boeing will decide to replace the 737, an aircraft based on 1960s-technology.

He also asks Boeing about the accuracy of reports that the company intends to seek to have lawsuits filed against it on behalf of victims of the Lion Air crash moved to Indonesia.