A high-ranking Boeing pilot who worked on the 737 Max three years ago during certification voiced doubts about the functionality that subsequently led to two fatal crashes. In the reports, which date from November 2016, the pilot describes his concerns about the MCAS system that he had tested in the flight simulator. That system automatically pushes the nose of the aircraft down if it rises too fast.

The U.S. Federal Aviation Administration reports that Boeing notified the transportation department of message traffic between the pilot and another aircraft manufacturer employee. The regulator said Boeing had been aware of the communications for months.

During the Verkaring the FAA writes that they consider the content of the report "worrying."

 "The FAA is also disappointed that Boeing did not immediately bring this document to the attention of its discovery."

avoid two crashes

Two crashes in less than five months - Lion Air Flight 610 on October 29 off the coast of Indonesia and Ethiopian Airlines Flight 302 on March 10 outside Addis Ababa - killed 346 people and led to the worldwide grounding of the 737 Max jets. Similar failures caused MCAS to repeatedly push the nose of the aircraft down until pilots lost control and the aircraft dived down in both situations.

While the disclosure of this news may not delay Boeing and FAA's efforts to return the plane to service, the stock fell 7% after the news of the messaging became known.

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