The Airco D.H.15 Gazelle was an experimental version of the D.H.9A, built as a flying test bed for a 500hp B.H.P. Atlantic twelve cylinder watercooled engine. This was an early example of a series of attempts between the wars to produce more powerful engines by bolting together two smaller engines – in this case two 230hp B.H.P. engines driving a single crankcase.
An order for two D.H.15s was placed on 7 September 1918, but only one was ever completed. The resulting aircraft was similar to the Liberty powered D.H.9A, and retained the standard armament of that aircraft. Tests with the completed aircraft during May 1920 showed that was faster and had a higher ceiling than the D.H.9A, but not by enough to justify further development.
Engine: One B.H.P. Atlantic twelve cylinder Vee engine
Wing span: 45ft 11 3/8in
Length: 29ft 11in
Tare Weight: 2,312lb
All-up weight: 4,773lb
Max Speed: 139mph
Service Ceiling: 20,000ft
Armament: One Lewis gun on Scarff ring in rear cockpit, one fixed forward firing Vickers Gun.