The Bristol Type 163 Buckingham was a British Second World War medium bomber for the Royal Air Force (RAF). Overtaken by events, it was built in small numbers and was used primarily for transport and liaison duties. In early 1939 Bristol suggested a bomber variant of the Beaufighter with their Hercules engines. British policy at the time was for medium bombers to be obtained from the US allowing British industry to concentrate on heavy bomber designs; nonetheless a design was requested preferably based on an existing aircraft. This meant working with the Beaufighter or Beaufort. Bristol worked on their design first as the Bristol Type 161 then the Type 162 Beaumont. Air Ministry specification B.7/40 called for a medium bomber to replace the Blenheim. The specification stipulated a speed of at least 300 mph at 5,000 ft, a normal load of 1,000 lb of bombs and a centre turret armed with at least two 0.5 inch (12.7 mm) machine guns. Only one manufacturer (Armstrong Whitworth) tendered a full design but it did not meet with approval. So when Bristol brought their Type 162 ("tentatively named Beaumont"), which was well matched to B.7/40, to the Air Staff, the company received a request to complete a mockup in 1940 and then a confirmed contract for three prototypes in February 1941. The Beaumont was based on the rear fuselage and tail of a Beaufighter, with a new centre and front fuselage. The armament was a mid-upper turret with four machine guns, with four more machine guns firing forward and two firing to the rear. Construction began in late 1940, with a new Air Ministry Specification B.2/41 to be written around it. Changes in the requirements, removing dive bombing and "direct army support" which incoming US bombers were expected to be capable of and increasing the performance to allow for the future, meant the Beaumont would no longer suffice. The changes in performance (requiring a bomb load of 4,000 lb, a speed of 360 mph and a range of 1,600 miles) meant a redesign by Bristol to use the Bristol Centaurus engine. The Bristol redesign with a larger wing and the more powerful engines was the Type 163 Buckingham. It had gun installations in the nose, dorsal and ventral turrets. Generally conventional in appearance, one unusual feature was that the bomb-aimer/navigator was housed in a mid-fuselage ventral gondola, resembling those on the earlier German Heinkel He 111H and American Boeing B-17C and -D in appearance. This was part of an attempt to give all the crew positions unobstructed views and access to each other's positions. The bomb bay could hold a 4,000 lb, two 2,000 lb, four 1,000 lb or six 500-lb bombs. The rear of the gondola had a hydraulically powered turret with two 0.303 Browning machine guns. The Bristol-designed dorsal turret carried four Brownings. A further four fixed, forward-firing Brownings were controlled by the pilot. Following more changes, specification B.2/41 was replaced by B.P/41. An order for 400, at an initial rate of 25 per month, was made with deliveries expected in March 1943 but Bristol were still concerned that this not a reasonable scale and would prove expensive, and as such complained to MAP about poor planning. The first flight took place on 4 February 1943. During testing, the Buckingham exhibited poor stability which led to the enlargement of the twin fins, along with other modifications. Variants Type 163 Buckingham Prototypes with two Centaurus IV engines, four built. Type 163 Buckingham B1 Production variant first flown 12 February 1944 with Centarus VI or XI engines, 400 ordered but reduced first to 300 then to 119, with only 54 built as bombers. Type 163 Buckingham C1 (Specifications below) Residual production completed as fast courier transport with four-passenger seats and removal of armour and armament and increased fuel tankage, 64 built. Type 164 Brigand Torpedo bomber variant using Buckingham wings and tails and new fuselage. Type 165 Brigand II Trainer variant of the Brigand, not built. Type 166 Buckmaster Trainer variant of the Buckingham. Type 169 Proposed photo-reconnaissance variant of the Buckingham, not built.