The DH18 was designed from the outset for use as a commercial transport, carrying a pilot and eight passengers. Its predecessors had simply been modified militay types, coverted to accept passengers.
The main cabin was enclosed in the centre fuselage, with the pilot seated in an open cockpit to the rear and was a single-engine biplane of large dimensions. The Napier Lion powerplant was housed in the nose section with wooden, 2 bay wire braced wings and a forward fuselage predominantly clad in plywood.
The prototype (G-EARI) first flew on 8th April 1920 and carried the construction number 1 of the newly formed De Havilland Aircraft Company. Unfortunately just 8 days later it was wrecked during a forced landing shortly after take off from Croydon Airport.
DH18s were initially delivered to Aircraft Transport and Travel Ltd (AT&T).
The second and third aircraft were initially constructed by Airco who were taken over by BSA when they eventually went bankrupt. BSA however decided against continuing aircraft production and the airframes were eventually completed at Stag Lane, Edgeware by the newly-formed De Havilland Aircraft Co Ltd. Built to order for Aircraft Transport and Travel (AT&T) these featured a number of minor modifications and carried the designation DH18A.
AT& T eventually folded in 1921 due to 'unfair competition' from French government backed airlines which forced the UK to commence its own state supported subsidised air services. Subsequently, the two AT&T DH18As were transferred to Instone Airlines, followed by a further example for their sole use.
2 further aircraft later were supplied to Instone to make up for a shortage in aircraft, these featuring plywood covered fuselages and being designated DH18B.
One aircraft was transferred to Daimler Airways for operation between Croydon and Paris. However, just 2 days into service, DH18A (G-EAWO) had the unhappy distinction of being destroyed in the first ever mid-air collision between commercial aircraft, coming together with Farman Goliath (F-GEAD) over northern France on 4th April 1922.
Production of all DH18 variants totalled 6 aircraft, the final survivor being the second machine (G-EARO), which flew at RAE Farnborough on miscellaneous trials until November 1927.
The DH18 eventually retired from commercial service in 1923 with one aircraft having flown 90,000 miles without incident. 2 examples were seconded to the Air Ministry and took part in 'Diching Trials' where on aircraft remain afloat for over 25 minutes.
|Powerplant||One 450 hp Napier Lion engine|
|Span||51 ft 3 in|
|Maximum Weight||DH18A 6,516 lb; DH18B 7,116 lb|
|Capacity||Pilot and seats for eight passengers in an enclosed cabin forward of the pilot|
|Maximum Speed||128 mph|
|Cruising Speed||100 mph|
|Range / Endurance||400 miles|
Number built & Variants
|DH18A||Three aircraft G-EARO, G-EAUF, G-EAWO|
|DH18B||Two aircraft with plywood-covered fuselages G-EAWW, G-EAWX|
SurvivorsThere are no known original survivors.