BOAC Flight 712

BOAC Flight 712 was a British Overseas Airways Corporation (BOAC) service operated by a Boeing 707 from London Heathrow Airport bound for Sydney via Zurich and Singapore. On Monday 8 April 1968, it suffered an engine failure on takeoff that quickly led to a major fire; the engine detached from the aircraft in flight. After the aircraft had made a successful emergency landing, confusion over checklists and distractions from the presence of a check pilot contributed to the deaths of 5 of the 127 on board. The direct cause of the fire was the failure of a compressor wheel, due to metal fatigue.

Flight attendant Barbara Jane Harrison was posthumously awarded the George Cross for heroism during the accident, another crew member received a British Empire Medal, and an air traffic controller was made a Member of the Most Excellent Order of the British Empire. As a result of the accident, BOAC changed certain aspects of its emergency procedure checklists.

Flight

Flight 712, scheduled to depart from Heathrow's Terminal 3 at 16:15 BST (15:15 GMT), took off from Runway 28L at 16:27 BST (15:27 GMT). It had 127 people aboard, including a crew augmented by the addition of an acting flight officer, John Hutchinson, and a check captain for routine performance review of the pilot in command, Captain Cliff Taylor. As well as the passengers, the aircraft was carrying baggage, mail and a radioactive isotope from the Isotope Production Unit at Harwell destined for the University Hospital in Jerusalem.

Seconds after takeoff from Heathrow's then-9000 ft runway 28L (extended, years later, and now re-designated as 27L), there was an unexpected bang and the aircraft started vibrating. The throttle controlling number two engine was shutting down. While Taylor ordered an engine failure drill, Flight Engineer Thomas Hicks carried out the engine failure drill, but both he and Check Captain Geoffrey Moss reached for the switch to cancel the undercarriage warning horn. At the same time, First Officer Francis Kirkland inadvertently cancelled the fire bell. Hicks reached for, but did not pull, the engine fire shut-off handle. Moss, observing the fire, exclaimed, "Bloody hell! The wing's on fire!"

In the control tower, the takeoff had been observed by John Davis, who saw what he initially thought was the sun reflecting off the aircraft's wing during its initial climb. Davis quickly realised that the aircraft was on fire. Davis instructed Flight 712 to make a left turn, with the intention that the aircraft would land on runway 28L. He hit the "crash button" which alerted the emergency services and declared an aircraft accident. The emergency services were informed of the type of aircraft involved and given a meeting point at which they were to assemble.

By this time, the windows on the port side at the rear of the fuselage were beginning to melt. As the aircraft flew over Thorpe the burning engine broke away from its mounting; no one on the ground was injured. At this time, the undercarriage was lowered and full flap selected. The flaps stopped three degrees short of their full travel. The aircraft was at a height of 3000 ft and flying at 225 kn. Cabin crew member Jennifer Suares repeated the emergency landing drill for passengers.

The crew realised that the aircraft would not last long enough to land back on 28L and declared a mayday at 16:29. Davis cleared the aircraft to land on runway 05R, which was 7733 ft long. He also instructed two other aircraft to perform a go-around, as runway 05R crossed runway 28R, which they were due to land on and Davis did not know whether Flight 712 would be able to stop before reaching that runway. The crew accepted Davis's offer of runway 05R, even though it was much shorter and not equipped with ILS. Taylor was able to safely land the aircraft on 05R, using wheel brakes and thrust reversing the outboard engines to halt the aircraft. The aircraft touched down about 400 yd beyond the threshold and stopped in 1400 yd. Taylor asked Davis for permission to evacuate, but the cabin crew were already opening the emergency doors. The flight crew started the fire drill, but the port wing exploded before this could be completed. As a result, the fire shut off handles were not pulled, and the booster pumps and electrical supply were left switched on. Due to the short period of time between the mayday being declared at 16:29 and the aircraft landing at 16:31, there was no time for the emergency services to lay a carpet of foam, which was standard practice at the time.