Авро Линкольн: Британдық ауыр бомбалаушысының тарихы

British four engined heavy bomber in service 1945 1963

The Avro Type 694 Lincoln is a British four engined heavy bomber, which first flew on 9 June 1944. Developed from the Avro Lancaster, the first Lincoln variants were initially known as the Lancaster IV and V; these were renamed Lincoln I and II. It was the 2nd last piston engined bomber operated by the Royal Air Force (RAF). The Lincoln attained operational status in August 1945. It had been initially assigned to units of the Tiger Force, a Commonwealth heavy bomber force which had been intended to play a role in the Japan campaign in the closing stages of the Second World War, but the war ended before the Lincoln could participate. Production of the type proceeded and the type was adopted in quantity, complementing and progressively replacing the Lancaster in RAF service during the late 1940s. The Lincoln was deployed on operations during the 1950s. RAF squadrons equipped with the type fought against guerrilla fighters during the Mau Mau Uprising in Kenya; the RAF and the Royal Australian Air Force (RAAF) also operated the Lincoln during the Malayan Emergency. The type also saw significant peacetime service with the RAF, RAAF and the Argentine Air Force. Lincolns were also operated in civil aviation, including use as aerial test beds for aero engine research. In RAF service, the Lincoln was replaced by a new generation of bombers using jet propulsion. In 1967, the last Lincoln bombers in Argentinian service were retired.

The Avro Lincoln originated from a design produced by Roy Chadwick as a development of the earlier Lancaster bomber which had been produced with the purpose of conforming with the requirements of the Specification B.14/43. Known initially as the Lancaster IV and Lancaster V, the envisioned aircraft, while bearing considerable similarity to the Lancaster, featured numerous improvements, such as the adoption of stronger, longer span, higher aspect ratio (10.30 compared with 8.02) wings along with two stage supercharged Rolls Royce Merlin 85 engines fitted within Universal Power Plant (UPP) installations. The prototype Lancaster IV, later renamed the Lincoln I, was assembled by Avro's experimental flight department at Manchester's Ringway Airport. According to aviation author Kev Delve, development of the Lincoln had proceeded relatively smoothly. Testing of the prototype quickly proved it to have favourable flight characteristics. A new emphasis was soon placed on 'quality over quantity' during the rationalisation process, seeking to employ fewer but more capable aircraft to perform their envisioned roles; while there was no longer any urgency in bringing new types of aircraft into service, limited procurement of equipment that fell within this ethos did proceed. Along with two additional Lincoln (Mk I and Mk II) aircraft on loan from the RAF, the type was briefly evaluated postwar by the RCAF. The Lancaster V/Lincoln II differed mainly in that it was fitted with Merlin 68A engines. Prior to the Lincoln being developed, the Australian government had already formulated plans for its Department of Aircraft Production (DAP), later known as the Government Aircraft Factory (GAF), to construct the earlier Lancaster Mk III. In its place, it was decided to proceed with manufacturing a variant of the Lincoln I to replace the Consolidated Liberators, which was re designated the Lincoln Mk 30. This model was manufactured between 1946 and 1949; it has the distinction of being the largest aircraft ever constructed in Australia. Orders for a total of 85 Mk 30 Lincolns were placed by the RAAF, although only 73 were ever produced. The first five Australian examples (A73–1 to A73–5), were assembled at Fishermans Bend using a large proportion of imported British made components. On 17 March 1946, A73 1 conducted its début flight; the first entirely Australian built Lincoln, A73 6, was formally delivered in November 1946. The Mk 30 initially featured four Merlin 85 engines, this arrangement was later changed to a combination of two outboard Merlin 66s and two inboard Merlin 85s. A further improved later version, designated Lincoln Mk 30A, featured a total of four Merlin 102s. During the 1950s, the RAAF heavily modified some of their Mk 30 aircraft to perform anti submarine warfare (ASW) missions, re designating them Lincoln GR. Mk 31. These examples had a 6 feet (2 m) longer nose to house acoustic submarine detection gear and its operators, larger fuel tanks to provide the aircraft with a 13 hour flight endurance and a modified bomb bay to accommodate torpedoes. According to pilot feedback, the Lincoln Mk 31 was particularly difficult to land at night, as the bomber had a tailwheel undercarriage and the long nose obstructed the pilot's view of the runway. In 1952, 18 aircraft were rebuilt to this standard, and were reallocated new serial numbers accordingly. Further aircraft were also derived from the Lincoln. A dedicated maritime patrol aircraft, designated the Avro Shackleton, was developed for the RAF and the South African Air Force (SAAF). Additionally, Avro decided to develop a commercial airliner, known as the Tudor, which harnessed elements of the Lincoln, such as its wings, in combination with various new elements, such as the adoption of a pressurised fuselage, to perform passenger operations.

During 1945, the RAF received its first Lincoln, which was delivered to No. 57 Squadron based at RAF East Kirkby, Lincolnshire. In August 1945, No. 75 (New Zealand) Squadron began to re equip with the Lincoln at RAF Spilsby, Lincolnshire. However, No. 75 (NZ) Sqn had received just three aircraft prior to VJ Day, and was disbanded quickly thereafter. Small numbers remained in use with Nos 7, 83 and 97 Squadrons until the end of 1955, at which point the type was phased out, having been replaced by the first of the V bombers. During the 1950s, RAF Lincolns participated in operations in Kenya against Mau Mau insurgents. During this action, they were operated from Eastleigh. The Lincoln was also deployed to Malaya during the Malayan Emergency, where it was used against insurgents aligned to the Malayan Communist Party. In Malayan theatre, RAF Lincolns were operated from Changi Air Base and Tengah Air Base. In excess of 3,000 sorties were flown during their 7 1/2 year deployment, during which half a million pounds of bombs dropped, 85 per cent of the total bomb tonnage dropped during the Malayan emergency. killing the seven crew members. In November 1955, four Lincolns of No. 7 Squadron RAF were detached for duties in British territories in the Middle East. In Bahrain, they carried out border patrols of the then Trucial States. When 7 Sqn was disbanded in December 1955, the four detached crews and aircraft became No. 1426 Flight RAF, officially a photographic reconnaissance unit. It was later sent to Aden, carrying out patrols in the lead up to the Aden Emergency. As the RAF Lincolns became unserviceable, primarily due to progressive wear and tear, they were replaced by a variety of jet powered aircraft. The Lincolns of Bomber Command were phased out from the mid 1950s and had been completely replaced by jet bombers by 1963. The last Lincolns in RAF service were five operated by No. 151 Squadron, Signals Command, at RAF Watton, Norfolk, which were retired on 12 March 1963. The adoption of the Lincoln effectively gave Argentina the most powerful bombing force in South America. Eighteen of these Lincolns were newly built, along with twelve ex RAF aircraft. In 1947, the type entered service with I Grupo de Bombardeo of V Brigada Aérea. By the beginning of 1965, eleven of these remained in operational use, the majority of these were retired during the next year. In 1967, the final examples of the Lincoln were retired. The Argentine aircraft were used in bombing missions against domestic rebels. Lincolns were deployed during an attempted military coup conducted in September 1951, the type was also used by both the government and rebel forces during the 1955 Revolución Libertadora coup which resulted in Argentinian President Juan Perón being deposed. In 1948, one of the bombers was returned to Avro for modification at RAF Langar in Nottinghamshire to allow it to operate these Antarctic support flights; the changes included the addition of Lancastrian nose and tail cones, additional fuel tanks, and removal of armament; this led to the aircraft becoming the first Avro Lincolnian.

Lincolns were frequently employed as testbeds in new jet engine development. RF403, RE339/G and SX972 flew with a pair of Armstrong Siddeley Python turboprops outboard in place of the Merlins, and was used for the ballistic casing drop test programme for the Blue Danube atomic weapon. SX972 was further modified to fly with a pair of Bristol Proteus turboprops. RA716/G had a similarly placed pair of Bristol Theseus turboprops and later also flew with Rolls Royce Avon turbojets replacing the pair of turboprops. Lincoln Test Bed RF530 kept its Merlins but had a Napier Naiad turboprop in the nose. It later flew, bearing the civilian "Class B" test registration G 37 1, with a similarly placed Rolls Royce Tyne which it displayed at the 1956 Society of British Aircraft Constructors (SBAC) show, making a low level flypast on just the nose Tyne, the four Merlins being shut down and propellers feathered. SX973 had a Napier Nomad diesel turbo compound installed in a similar nose mounted installation. RA643 flew with a Bristol Phoebus turbojet in the bomb bay, and SX971 had an afterburning Rolls Royce Derwent mounted ventrally.