United Airlines Flight 811
https://en.wikipedia.org/wiki/United_Airlines_Flight_811
The aircraft had been flying for 17 minutes,
[1]: 25 as it was passing from 22,000 to 23,000 feet (6,700 to 7,000 m), when the flight crew heard a loud "thump", which shook the plane.
[1]: 2 About a second and a half later, the forward cargo door blew off. It swung out with such force that it tore a hole in the fuselage. Pressure differentials and aerodynamic forces caused the cabin floor to cave in, and 10 seats (G and H of rows 8 through 12) were ejected from the cabin.
[1]: 8
[9] All eight passengers seated in these locations were ejected from the aircraft, as was the passenger in seat 9F. Seats 8G and 12G were unoccupied.
[1]: 109
[9] A gaping hole was left in the aircraft, through which a flight attendant, Mae Sapolu in the business-class cabin, was almost blown out. Purser Laura Brentlinger hung on to the steps leading to the upper deck, and was dangling from them when the decompression occurred. Passengers and crew members saw her clinging to a seat leg and were able to pull her back inside the cabin, although she was severely injured.
[9]
The pilots initially believed that a bomb had gone off inside the airliner, as this accident happened just two months after
Pan Am Flight 103 was blown up over
Lockerbie,
Scotland. They began an emergency descent to reach an altitude where the air was breathable, while also performing a 180° left turn to fly back to Honolulu.
[1]: 2 The explosion damaged components of the on-board emergency oxygen supply system, as it was primarily located in the forward cargo sidewall area, just aft of the cargo door.
[1]: 8