According to a preliminary report, the Delta Air Lines plane that landed belly-up at Toronto’s Pearson International Airport last month was descending at a high rate of speed as its landing gear collapsed,

Investigators say a high-speed descent led to a landing gear collapse that caused a Delta Air Lines plane to flip upside down in Toronto in February.

The proximity warning system aboard the Delta Air Lines flight that crashed at Pearson airport last month sent an alert indicating a high rate of descent less than three seconds before the plane touched down,