In 1934, the Air Ministry issued a specification for a light day-bomber also capable of providing close air-support.
Accordingly, Hawker Aircraft and Fairey Aviation submitted designs, the former offering a two-seat machine similar in size and general concept, to its interceptor then in development (which would evolve into the Hurricane).
The outer wings and tailplane of both designs were built on identical jigs, although the Hawker Hurricane eight-gun battery was deleted for the Hawker Henley, as the light-bomber was eventually named. The Hawker Henley's armament initially comprised a wing-mounted Vickers machine-gun and a Lewis gun in the rear cockpit. The wing was set in a low mid-fuselage position, enabling the stowage of up to 550lb of bombs within the fuselage and with provision for another 200lb of bombs to be carried on underwing racks.
Construction of the Hawker Henley prototype (K5115) commenced at Hawker’s Kingston factory in mid-1935, and was powered by a Rolls-Royce Merlin engine. It made its first flight from Brooklands on 10th March 1937.
Initially, it was flown with fabric-covered wings although it was later fitted with metal wings during August 1937. The design was of all-metal construction, with fabric-covered rear fuselage and tail similar to the Hurricane.
Showing a great deal of promise, the Hawker Henley was the subject of a production order for 350 with Gloster Aircraft at Hucclecote taking on construction duties.
A second prototype Hawker Henley (K7554) was flown in May 1938, but a change in the Air Ministry’s policy on the role of the light day-bomber saw the Henley relegated to second-line duties, predominantly as a target-tug. The aircraft (K7554) was converted into the prototype Hawker Henley TT.III, with a windmill device on the port side of the rear cockpit, used to reel in the drogue target.
The earlier production order was subsequently reduced to 200 with the type entering RAF service in November 1938.
Although a great improvement over the tired target-towing biplanes, the Hawker Henley nevertheless struggled to maintain a steady towing speed of 220 m.p.h. (355km/h) without its Merlin engine overheating. It was thus found to be less than useful for the training of pilots in much faster fighters.
As a result, they were sent to Anti-Aircraft Co-operation Units from late 1943, where they fared worse if anything, owing to the larger drogue targets they were required to tow. Having suffered an unusually high attrition rate throughout its career, the Hawker Henley was finally withdrawn from service altogether in April 1945.
The Hawker Henley was also used as an engine testbed, the original prototype (K5115) being fitted with a Rolls-Royce Vulture, 24-cylinder engine in 1939. This engine proved troublesome however, and another example (L3302) was also similarly converted during the following year.
Additionally in 1940, a Hawker Henley (L3414) was fitted with a Rolls-Royce Griffon engine and was used for much of the engine trials work carried out for its further use in the Fairey Firefly.
The history of the Hawker Henley has always been the source of a certain amount of speculation and mystery. Questions were often raised about why the (arguably) much less capable Fairey Battle was selected to undertake certain duties, when they would have been far better suited to the faster and more capable Hawker Henley.
Variants & Numbers
|Henley Mk I||First prototype K5115|
|Henley Mk II||Second prototype K7554|
|Henley Mk III||Production target-tug aircraft. 200 built|
|Total built||202 aircraft|
|Powerplant||One 1,030 hp Rolls-Royce Merlin II or III liquid-cooled engine|
|Capacity and armament||Two crew (pilot, and observer/gunner); unarmed in target tug role|
|Maximum speed||272 mph with air-to-air drogue at 17,500ft|