Bristol Beaufort

The Bristol Beaufort (manufacturer designation Type 152) was a British twin-engined torpedo bomber designed by the Bristol Aeroplane Company, and developed from experience gained designing and building the earlier Blenheim light bomber.

Beauforts first saw service with Royal Air Force Coastal Command and then the Royal Navy Fleet Air Arm from 1940. They were used as torpedo bombers, conventional bombers and mine-layers until 1942, when they were removed from active service and were then used as trainer aircraft until being declared obsolete in 1945. Beauforts also saw considerable action in the Mediterranean; Beaufort squadrons based in Egypt and on Malta helped interdict Axis shipping supplying Rommel's Deutsches Afrikakorps in North Africa.

Beauforts saw their most extensive use with the Royal Australian Air Force in the Pacific theatre, where they were used until the very end of the war. With the exception of six examples delivered from the United Kingdom, Australian Beauforts were locally produced under licence.

Although designed as a torpedo-bomber, the Beaufort more often flew as a level-bomber. The Beaufort also flew more hours in training than on operational missions, and more were lost through accidents and mechanical failures than were lost to enemy fire. However, the Beaufort did spawn a long-range heavy fighter variant called the Beaufighter, which proved to be very successful and many Beaufort units eventually converted to the Beaufighter.

Although it did see some use in the torpedo bomber role, including attacks on the battleships Scharnhorst and Gneisenau while in port in Brest, the Beaufort more often used bombs while in European service.

In early 1940, 22 Squadron equipped with Vildebeests, began to receive Beauforts. The Beaufort was a much faster, heavier aircraft than the biplane and the crews needed a great deal of training in torpedo-dropping using new techniques required by the Beaufort. The lighter, slower Vildebeest was able to dive then flatten out before launching the torpedo; Beauforts carried too much speed after diving so it needed a longer, level approach to the torpedo drop.

Because of this, and because of a shortage of torpedoes the squadron's first operations consisted of laying magnetic mines ("Gardening" in RAF parlance) and dropping conventional bombs. As an alternative to the torpedo the Beaufort could carry a 2,000 lb (910 kg) bomb using a purpose built carrier. On one of its first bombing operations, on 7 May 1940, a Beaufort dropped the first British 2,000 lb (910 kg) bomb, aiming at a German cruiser anchored off Norderney.

The first Beaufort operation took place on the night of 15/16 April, when nine Beauforts successfully laid mines in the Schillig Roads (north of Wilhelmshaven). One Beaufort failed to return. A second unit, 42 Squadron began to re-equip with Beauforts, starting in April. The Beaufort, however still had teething problems and, after some Beauforts were lost in mysterious circumstances, a Court of Enquiry in June 1940 concluded that the Taurus engines were still unreliable and both operational squadrons were grounded until the engines could be modified.

The first RAF torpedo attack of the war came on 11 September 1940, when five aircraft of 22 Squadron attacked a convoy of three merchant ships off Ostend (Oostende in Belgium). One torpedo hit a 6,000 ton (5,440 tonne) ship. Four days later, the first "Rover" was mounted; a Rover was an armed reconnaissance mission carried out against enemy shipping by a small number of aircraft operating independently. "Rovers" became a major part of Beaufort operations over the next 18 months. Other more hazardous operations were to follow, with one Beaufort pilot being awarded a posthumous VC.

The only other UK based units to be equipped and fly operationally with the Beaufort, 86 Squadron and 217 Squadron, were operational by the middle of 1941. Beauforts also equipped some Commonwealth Article XV squadrons serving within the RAF, but, because of supply shortages, were replaced by other aircraft types before the units flew operationally.

A successful torpedo drop required that the approach run to the target needed to be straight and at a speed and height where the torpedo would enter the water smoothly: too high or too low and the torpedo could "porpoise" (skip through the water), dive, or even break up. Height over the water had to be judged without the benefit of a radio altimeter and misjudgement was easy, especially in calm conditions. For the Beauforts using the 18-inch (450-mm) Mk XII aerial torpedo, the average drop-height was 68 ft (21 m) and the average range of release was 670 yd (610 m).

During the run-in, the aircraft was vulnerable to defensive anti-aircraft fire, and it took courage to fly through it with no chance of evasive manoeuvres. The Beaufort's optimum torpedo dropping speed was a great deal higher than that of the Vildebeests it was replacing, and it took practice to accurately judge the range to, and speed of, the target ship. A ship the size and speed of Scharnhorst, for example, would look huge, filling the windscreen at well over 1 mi (1.6 km) and it was easy to underestimate the range. 

In action, torpedoes were often released too far away from the target, although there was one recorded instance of a torpedo being released too close. For safety reasons, torpedo warheads had a set distance (usually about 300 yd/274 m) from the release point before they were armed. It also took some distance for the torpedo to settle to its running depth.

Once the torpedo had been dropped, if there was room, a sharp turn away from the enemy was possible: more often than not the aircraft had to fly around or over the ship, usually at full-throttle and below mast height. A sharp pull-up could be fatal, as it could expose a large area of the aircraft to anti-aircraft guns.
                    

                
General characteristics
Crew: 4
Length: 13.46 m
Wingspan: 17.63 m
Height: 4.34 m
Wing area: 46.73 m²
Empty weight: 5,945 kg
Loaded weight: 9,629 kg
Powerplant: 2 × Bristol Taurus II, III, VI, XII or XVI 14-Cylinder sleeve valve radial engine, 1,130 hp (843 kW) each
Maximum speed: 420 km/h 2000 m
Cruise speed: 410 km/h 2000 m
Range: 2,600 km
Service ceiling: 5,030 m
Rate of climb: 6.1 m/s
Wing loading: 206 kg/m²
Power/mass: 0.175 kW/kg
Guns: 3 x 7.7 mm Vickers GO machine guns (two in Bristol Mk IV dorsal turret, one in port wing) 
or; 6 x 7.7 mm Vickers GO mg. Two fixed in nose, two in turret, one in port wing and one firing laterally from entry hatch. 
Late production. 1 x 7.7 mm Browning machine gun in rear-firing chin blister
Bombs: 730 kg 18 in Mk XII torpedo, or 900 kg of bombs or mines.