The Downend air crash occurred on 6 November 1957 when a prototype Bristol Britannia

Bristol Britannia

The Bristol Type 175 Britannia was a British medium-to-long-range airliner built by the Bristol Aeroplane Company in 1952 to fly across the British Empire...

 aircraft crashed in woods near Overndale Road in Downend Village, near Bristol

Bristol

Bristol is a city, unitary authority area and ceremonial county in South West England, with an estimated population of 433,100 for the unitary authority in 2009, and a surrounding Larger Urban Zone with an estimated 1,070,000 residents in 2007...

, England, on its landing approach at Filton airport during a test flight. All fifteen onboard, four crew and 11 technicians died in the crash.

A memorial service was held at Bristol Cathedral

Bristol Cathedral

The Cathedral Church of the Holy and Undivided Trinity is the Church of England cathedral in the city of Bristol, England, and is commonly known as Bristol Cathedral...

on 19 November 1957. A memorial plaque at the crash site, now called Britannia Wood, was unveiled on 3 November 2007 by the widow of the aircraft's pilot.

Cause

The exact cause of the crash was never determined, but was suspected to be a malfunction of the autopilot, possibly due to faulty wiring. The company which manufactured the autopilot system issued a statement claiming it was not due to the autopilot system, but still altered the system in newer aircraft; the official report states unknown cause but "the autopilot system cannot be ruled out as the likely cause".

Another source cites the cause as "...an instrument failure which ultimately led to a loss of control."

Casualties

The 15-man crew perished in the crash. Despite the aircraft coming down in a residential area, nobody was killed on the ground. One lady, an occupant of Overndale Road, was taken to hospital when out hanging washing on the line in the garden was hurt by the impact blast when one of the engines and part of the wing landed next to the house.