Trans-Canada Air Lines was the first North American airline to accept delivery of the Viscount.

[3] On the morning of July 9, while the aircraft was cruising at flight level 190 over the town of Flat Rock, Michigan, the No.

One of the four propeller blades penetrated the passenger cabin and cut through the first row of seats, immediately killing a young woman travelling with her two small children.

The blade also injured a family of three sitting across the aisle from the victim and a flight attendant who had been standing at the front of the cabin.

[3] Canadian accident investigators found that a bevel gear in the oil pump drive had failed, shutting off lubrication to the propeller.

[3] The possibility of the bevel gear drive failing causing the propeller to windmill had not been foreseen by Vickers engineers, and there was therefore no mention of it in the training or operations manual.