Boeing is under fire for releasing information about safety incidents still under investigation by the US National Transportation Safety Board, including details the agency describes as inaccurate. 

In a 27 June letter to David Calhoun, Boeing’s chief executive, the NTSB elaborates on its assertion that the airframer “blatantly violated NTSB investigative regulations” when it publicly disclosed information relevant to the investigation of the 5 January Alaska Airlines Boeing 737 Max 9 door-plug blowout.

The agency also takes issue with Boeing’s recent statements regarding a “Dutch roll” on a 737 Max 8 operated by Southwest Airlines

“Parties to an NTSB investigation are restricted from releasing any investigative information without the NTSB’s express approval,” the letter says. ”This includes both on- and off-the-record statements and interviews.”

Boeing's 737 Renton site 25 June 2024

Source: Jennifer Buchanan, Seattle Times

Boeing briefed reporters on 25 June at its production facility in Renton, Washington and shared information the NTSB describes as inaccurate 

Boeing’s senior vice-president of quality Elizabeth Lund provided reporters with more details on the door-plug incident on 25 June at the company’s 737 production site in Renton, insisting that Boeing has since improved the quality and safety of the commercial jets rolling off production lines. 

The NTSB cites that briefing as taking place “without knowledge or consent of the NTSB”, and says the information shared included “unsubstantiated speculations about possible causes” of the incident. 

”We have verified that part of the released information was either inaccurate or unknown to the NTSB, while other parts were not previously disclosed to the public,” the letter says. 

Other recent statements made by Howard McKenzie, Boeing’s chief engineer, are cited as breaching the NTSB’s disclosure policies.

McKenzie maintained that a 25 May incident involving a Southwest Airlines 737 Max 8 which experienced a Dutch roll – a rare event that involves an aircraft yawing and rolling at the same time – was due to factors specific to the aircraft involved rather than the jet’s design or to its production system.

The NTSB challenges that assertion: “Specifically, Mr McKenzie stated that the event has nothing to do with design or manufacturing.’ The NTSB has not made any such determination, and our investigators have not yet ruled out design or manufacturing issues as contributing to this event.” 

The letter represents the second warning Boeing has received this year regarding the “flagrant violation ” of NTSB rules, it says. 

“It is crucial that the investigation speaks with one voice – that of the NTSB – to prevent the release of inaccurate, misleading, unconfirmed and out-of-context investigative information to the media, public and lawmaker, which is exactly what occurred during Boeing’s media briefing,” the NTSB says. 

“In the briefing, Boeing also portrayed the NTSB investigation as a search to locate the individual responsible for the door plug work,” it adds. “This is false and misleads the public regarding the purpose and scope of the NTSB’s purposes.”

The agency asserts that it is focused on pinpointing the probable cause of the accident rather than assigning liability. 

Lund is expected to appear during an investigative hearing on the case scheduled for 6-7 August in Washington, DC. Boeing will not be a party to the hearing “and therefore will not be allowed to ask questions of other participants”, the NTSB says. 

The agency has also notified the US Department of Justice regarding the unauthorised release of information regarding Alaska flight 1282.