Hawker Henley

With the Air Ministry requiring a high speed light bomber to operate in a close support role at a speed of around 300 mph Specification P.4/34 was issued during February 1934 with Fairey, Gloster and Hawker all competing. Hawker, at this time, were well advanced with the development of their Hurricane fighter, and the design Hawker submitted, known as the Henley, would share outer wing and tailplane jigs with the Hurricane, this would provide both production and economy benefits, and the Henley would also have its power supplied by the Rolls-Royce Merlin.

Housing a crew of two, pilot and observer/air gunner, the Henley was able to carry 750lb of bombs, 550lb inside the fuselage and 200lb under the wings. With Hawker giving their Hurricane fighter priority, the Henley prototype would not fly until the 10th March 1937, nearly two years after construction began during the middle of 1935. Originally fitted with a Rolls-Royce Merlin 'F' engine, which would become the Merlin I, the overall performance of the aircraft would prove excellent, and an order for 350 aircraft was placed.

During 1937 the Fairey Battle light bomber entered Royal Air Force service, so the Air Ministry no longer needed an aircraft to fulfil this role. Instead it would be used as a target tug, and so the second Hawker Henley prototype was converted for this role, and on the 26th May 1938 made its first flight. The original order for 350 aircraft was changed to just 200 Henleys, to be built as target tugs. The following year saw the first prototype refitted with a Rolls-Royce Vulture II engine, and this flew for the first time on the 17th April 1939.

Known as the Henley Mk III, the target tug variant would be the only one to enter production. Powered by the 1,030-hp Rolls-Royce Merlin II or III engine, it had a top speed of 272 mph, range of 950 miles with a service ceiling of 27,000 ft and had no armament. First entering service with Nos. 1, 5 and 10 Air Gunnery Schools, a major flaw was soon discovered with the aircraft. The Henley was susceptible to engine failure when it towed at a speed of 220 mph.

As a result the Henley would be transferred to Anti-Aircraft Co-operation units to tow drogue targets. It was discovered that it was even more unsuited to the role and after suffering the loss of several Henleys due to the engines cutting out and not being able to release the drogue quick enough, the aircraft was withdrawn and replaced by Boulton Paul Defiants converted for the role and Miles Martinets.

By the time production ended 202 examples of the aircraft had been built.