The Bristol Blenheim was a light bomber based on designs for a fast, twin engined, passenger aircraft. When, in 1937, the Blenheim entered service with the RAF it was the first RAF aircraft to have an all metal stressed skin and one of the first to incorporate a retractable undercarriage, variable pitch propellers, flaps and a power operated gun turret. It was also at this date, one of the fastest bombers of its day.

When first designed it was envisaged that the Blenheim would be faster than defending fighters but by 1939 this was not the case. Despite this, the Blenheim was moderately successful both as a bomber and maritime patrol aircraft.

By 1939 the Blenheim was also developed as a heavy fighter, but like its Luftwaffe contemporary, the twin engine Messcherscmitt Bf 110, found itself outclassed by its more agile single engine opponents leading to its withdrawal from day operations. Like the Messerchmitt Bf 110 the Blenheim was, however, developed into a successful nightfighter design, and it was as a night fighter that it achieved successes with 600 City of London Auxiliary Squadron at Hornchurch.

The nightfighter variant, such as that flown by 600 Squadron, carried an additional gun pack of four .303/7.7 mm machine guns in addition to its normal armament. Some of 600 Squadrons Blenheims were also equipped with the worlds first air interception radar, the AI MkIII. The Blenheim remained the mainstay of Britain’s night fighter force until its gradual replacement by the faster and more agile Bristol Beaufighter and De Havilland Mosquito.

By 1943 the Blenheim had been replaced in almost all its frontline duties but continued in service as a trainer. There are presently no airworthy examples, although static examples can be seen at the Imperial War Museum, Duxford and the RAF Museum, Hendon.

The statistics below are for the Blenheim 1F night fighter variant as flown by 600 Squadron.

Type: Heavy Night Fighter
Crew; 3
Powerplant. 2 x 920 hp Bristol Mercury XV radials
Maximum Speed: 266 mph
Maximum Altitude: c 31,500 feet
Range: c 1,125 miles
Armament: 4 x .303/7.7mm Browning machine guns in under fuselage pod