Blame Dennis Muilenburg. In his (successful) efforts to get the Boeing stock price up, he got rid of all the senior engineers who would have known better than

Blame Dennis Muilenburg. In his (successful) efforts to get the Boeing stock price up, he got rid of all the senior engineers who would have known better than to make a non-redundant control system responsible for human flight safety. (The MCAS used input from only one AOA sensor.)