(CNN) -- Boeing has released a trove of more than 100 pages of internal company communications that further casts the company's actions around the troubled 737 Max in a bad light.
The documents were sent Thursday to the House and Senate committees that have been probing Boeing's design of the plane. They were also released by the company to the media. The company's release included an apology for the content of the documents.
"These communications do not reflect the company we are and need to be, and they are completely unacceptable," said Boeing. "We regret the content of these communications, and apologize to the [Federal Aviation Administration], Congress, our airline customers, and to the flying public for them."
Many of the documents revolve around the development and qualification of 737 Max simulators in 2017 and 2018.
"These communications contain provocative language, and, in certain instances, raise questions about Boeing's interactions with the FAA in connection with the simulator qualification process." But Boeing said it is "confident in the regulatory process for qualifying these simulators."
Problems with the 737 Max led to two fatal crashes and the loss of 346 lives. The planes have been grounded since March, costing the company billions of dollars so far. The crisis cost former CEO Dennis Muilenburg his job. His successor, David Calhoun, will start as CEO on Monday.
The company statement raises the possibility that the documents could further delay its 10-month effort to get approval for the 737 Max to fly once again.
"We welcome, and will fully support, any additional review the FAA believes is appropriate in connection with any of these matters, as well as the continued involvement of the relevant congressional committees with these issues."