Major air safety failures and last-minute mistakes caused Thursday night’s midair collision over the Potomac River that left 67 people dead, according to expert observers and officials. Late Wednesday night,

At about 9pm local time (02:00 GMT) on Wednesday, an inbound American Airlines aircraft (flight 5342), manufactured by the Canadian firm Bombardier, collided with a Sikorsky Black Hawk army helicopter as it approached the Ronald Reagan airport, located along the Potomac River southwest of Washington, DC.

Ryan O’Hara, a father-of-one, was one of the three soldiers aboard the military helicopter, according to reports