The prototype De Havilland DH50 G-EBFN ground running at Stag Lane.
Designed and built in the early 1920s by the De Havilland Aircraft Company
at Stag Lane, Edgware, this large single engine transport biplane was one of the first successful designs to emerge from the newly formed company.
The first prototype De Havilland DH50 (G-EBFN) flew on 30th July 1923, powered by a water-cooled 230 hp Siddeley Puma engine. The aircraft was an immediate success and won the 1924 King’s Cup Air Race at Lee-on-Solent, flown by aviation pioneer Alan Cobham at an average of 106 mph. Cobham later flew the aircraft to Tangier and back in just 28 flying hours and followed this with a non-stop flight from London to Madrid.
The De Havilland DH50 was designed to replace the aged DH9C
aircraft being used by the De Havilland Hire Service. It accommodated 3 passengers in a glazed, enclosed cabin in the centre of the fuselage, whilst the pilot is seated in an open cockpit to the rear. The type possessed both excellent handling qualities and performance and it was very popular with both pilot and passenger.
Alan Cobham made a further number of pioneering, record flights before replacing it with the second aircraft (G-EBFO), fitted with a 385 hp Armstrong Siddeley Jaguar engine and re-designated as the De Havilland DH50J.
The De Havilland DH50J became famous in Cobham's hands, especially during his long-distance route-proving flights. One expedition was the 17,000 miles to Rangoon and back during the winter of 1924-25, an adventure which subsequently earned him a knighthood. Cobham subsequently piloted the aircraft on a 16,000 mile flight from Croydon to Cape Town between November 1925 and February 1926.
One aircraft was fitted with twin floats in readiness for a survey flight of Australia in 1926. Unfortunately, the venture was marred with tragedy when Cobham's engineer (AB Elliott) was shot and killed as they overflew the desert between Baghdad and Basra.
Cobham flew onto Australia and back between 30th June and 1st October 1926. Upon its return after these ‘Empire flights’ (totalling a distance of 62,000 miles) the aircraft (G-EBFO) was landed on the River Thames, alongside the Palace of Westminster and the Houses of Parliament.
Crowds line the streets to see Sir Alan Cobham's De Havilland DH50J after its Empire flights.
The initial production variant was the De Havilland DH50A which had a slightly enlarged cabin, increased radiator area and other minor modifications. Nine DH50A's' were delivered into Australia and it was their reliability and performance that led to the National Airline QANTAS taking out a production licence for the type.
Production of all variants totalled 17 built in Britain, 11 in Australia, 3 in Belgium and 7 in Czechoslovakia, where they were used by the airline CSA (Ceskoslovenske Statni Aeroline).
The type was operated by SABENA, Imperial Airways and Northern Air Lines as well as Air Taxis Ltd, Brooklands School of Flying and the Iraq Petroleum Transport Company Ltd.
De Havilland DH50 G-EBFP outside the Imperial Airways hangar at Croydon.
Three of the QANTAS-built aircraft were built with Bristol Jupiter VI engines although these were known as DH50J’s, despite having a different engine from Cobham's original Jaguar-equipped DH50J.
Australian De Havilland DH50A G-AUAY photographed at Melbourne.
One British-built Qantas DH50 (G-AUER / VH-UER) was modified at the De Havilland facility in Queensland to suit the requirement of the Australian Inland Mission, serving as an Air Ambulance in what was better known as The Royal Flying Doctor Service of Australia.
The last QANTAS-built DH50J VH-ULG ‘Hippomenes’ at Longreach, Queensland in August 1929.
Despite a reasonably low production number (37 in total), the design saw success in six countries around the world and served with both the Royal Australian and Royal New Zealand Air Forces.