The deadly Boeing 737 Max crashes in 2018 and 2019 involved a software system, MCAS, that was supposed to keep people safe — but instead contributed to the tragic deaths of 346 people. Watch an excerpt from "Boeing’s Fatal Flaw," a documentary from FRONTLINE and The New York Times premiering Sept. 14, 2021.

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For the full story, watch "Boeing’s Fatal Flaw" starting Sept. 14 on FRONTLINE: https://to.pbs.org/3z53A0h

"Boeing’s Fatal Flaw" is a FRONTLINE production with The New York Times and Left/Right Docs. The writer and director is Tom Jennings. The producers are Vanessa Fica and Kate McCormick. The reporters are David Gelles, James Glanz, Natalie Kitroeff and Jack Nicas. The senior producer is Frank Koughan. The executive producers for Left/Right Docs are Ken Druckerman and Banks Tarver. The executive producer of FRONTLINE is Raney Aronson-Rath.

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FRONTLINE is produced at GBH in Boston and is broadcast nationwide on PBS. Funding for FRONTLINE is provided through the support of PBS viewers and by the Corporation for Public Broadcasting. Major funding for FRONTLINE is provided by the Ford Foundation. Additional funding is provided by the Abrams Foundation; the John D. and Catherine T. MacArthur Foundation; Park Foundation; and the FRONTLINE Journalism Fund with major support from Jon and Jo Ann Hagler on behalf of the Jon L. Hagler Foundation and additional support from Koo and Patricia Yuen.