The designation D.H.17 was allocated
to a project for a twin-engined 16-passenger
biplane which was not built. The
next type number, de Havilland
D.H.18, was allocated to a large singleengined
biplane accommodating eight
passengers in an enclosed cabin; the
pilot was seated in an open cockpit
behind the wings. Built at Hendon, the
D.H.18 first flew early in 1920 and was
delivered to Aircraft Transport & Travel
Ltd for use on the Croydon-Paris service.
However, this D.H.18 had a short life,
terminated by a forced landing near
Croydon in August of the same year.
During 1920 the Aircraft Manufacturing
Company, which had been building
de Havilland designs, was re-formed as
the de Havilland Aircraft Company Ltd.
The new organisation built two modified
aircraft designated D.H.18Aforlnstone
Air Line, followed by a third. These were
kept busy on Continental services until
the first, having accumulated high flying
hours, was withdrawn from use in September
1921; another was lost in a crash
only two months after delivery. The third
production D.H.18A, delivered to Instone
in June 1921, was passed to Daimler
Hire Ltd in April 1922, only to be destroyed
over France a few days later in a
mid-air collision with a Farman Goliath.
The last two aircraft were designated
D.H.18B, and had plywood-covered
fuselages and increased weights; they
served with Instone for a short time
before the second was dismantled in
1923. The first was used in Air Ministry
flotation tests, being deliberately landed
in the sea off Felixstowe in May 1924.
Strangely, the last surviving D.H.18 was
the first production aircraft which, following
its withdrawal from Instone's use
in 1921, was delivered to RAE Farnborough
for test purposes. It was finally
scrapped in 1927.
