Armstrong Whitworth F.K.9

The F.K.9 two-seat fighter-reconnaissance quadruplane was built by Sir W G Armstrong Whitworth & Co Ltd as a private venture, and was initially flown in the summer of 1916. Initial trials dictated a number of modifications, including new wings with enlarged ailerons, an enlarged fin, a redesigned engine cowling and increased undercarriage track. In this form, powered by a 110hp Clerget 9Z rotary engine, and with a designated armament of one fixed 7.7mm Vickers gun and one free 7.7mm Lewis gun, the F.K.9 was officially tested in November-December 1916 at the Central Flying School. A production contract for 50 examples of an improved version, the F.K.10, was awarded.