The Professional Aviation Safety Specialists (PASS), the union representing some staff units within the Federal Aviation Administration (FAA), termed the messages "disheartening" and called for re-evaluation of the increased delegation of oversight granted by regulators to Boeing for airplane development.
U.S. Senator Maria Cantwell, D-Wash., said she is "deeply concerned" by the documents and Boeing's apparent intent "to work around the FAA and foreign regulators."
Members of the U.S. House of Representatives were particularly incensed by one document showing that, in order to avoid any need for additional pilot training, Boeing downplayed to the FAA the significance of the new flight control software on the Max -- known as the Maneuvering Characteristics Augmentation System (MCAS) -- that was implicated in the two crash flights.
House Transportation and Infrastructure Committee vice-chair Rep. Rick Larsen, D-Everett, said these "efforts to characterize the MCAS software as seemingly inconsequential were a serious mistake."
He called for Congress to pull back some of Boeing's authority to handle oversight of its own jet programs, a move that would likely slow certification of its upcoming new airplane, the Everett-built 777X.
Most of the documents made public Thursday were forwarded to Congress, the Department of Justice and the FAA in late December, the same day that Boeing fired Dennis Muilenburg as CEO. Boeing added some more documents with the release.
All the documents came out of a group within Boeing that worked during development of the 737 Max to get the flight simulators qualified by regulators and to determine the training that would be required for an airline pilot to move from the previous 737 model to the Max.
Many of the messages are from then-737 chief technical pilot Mark Forkner, including some late-night instant message exchanges with his deputy, Patrik Gustavsson, similar in tone to conversations released in October that sparked outrage then.
In the newly released exchanges, with Forkner sometimes drinking Grey Goose vodka -- "I just like airplanes, football, chicks and vodka, not in that order," he wrote -- and Gustavsson preferring Bowmore Scotch, both talk loosely about their bosses and everyone else they have to deal with in varying derogatory ways.