Early production Avro 694 Lincoln RA638 on flight test in August 1945.
Although the Avro Lancaster was still the spearhead of Bomber Command’s offensive power in 1943, the Air Ministry drew up specification B14/43 to cover its replacement. Known originally as the Lancaster IV, Avro’s new design was for a long-range high-altitude development of the earlier aircraft, to be powered by Rolls-Royce Merlin 85 engines.
A number of Lancaster components were used, but the extent of the changes was such that the machine became identified as the Type 694 Lincoln. A new wing of increased span and higher aspect ratio was fitted to a longer fuselage, heavier armament was to be carried and, as gross weight rose, a stronger landing gear was required. The unarmed first prototype was flown by Captain H. A. Brown at Ringway, Manchester, on 9 .June 1944 and four days later was delivered to Boscombe Down for service trials. A Martin dorsal turret was later added, although this was to be replaced by a Bristol turret in the other prototypes and production Lincolns. The second prototype was flown on 13 November 1944 and plans were made to produce a total of 2,254 aircraft by Avro at Chadderton and Yeadon, by Metropolitan Vickers at Trafford Park, and by Armstrong Whitworth’s factories at Baginton and Bitteswell. In fact, British production totalled three prototypes, 72 Mk Is and 465 Mk IIs: the last of the 168 Avro-built Lincolns was delivered in the spring of 1946 and the last of 299 from Armstrong Whitworth’s line on 5 April 1951. In 1947, 40 aircraft were exported to Argentina and remained in service with the Argentine Air Force until 1967. 12 of these aircraft were diverted from RAF orders with the remaining 18 being new-built aircraft manufactured by Armstrong Whitworth. One Mk XV was completed by Victory Aircraft in Canada and the Government Aircraft Factory in Australia produced 43 Mk 30s and 30 Mk 30As. In 1951 20 Australian aircraft were fitted with a 6 ft 6 in (1.98 m) nose extension to house two radar operators and their equipment, with the designation Mk 31.
Three prototypes and 162 production Lincoln bombers were built by Avro in Manchester with a further 6 at Yeadon, 80 at Metropolitan-Vickers and 229 at Armstrong Whitworth in Coventry (18 of these being for export to Argentina). In addition, 73 were constructed by the Australian Government Aircraft Factory in Melbourne with a further single example being built by Victory Aircraft Ltd in Canada.
The first Australian Lincoln B.Mk 30 built by the Beaufort Division of the Department of Aircraft Construction, flew on 17th March 1946.
Around a dozen Lincolns acted as engine flying test beds for the Armstrong Siddeley Python, Bristol Phoebus, Theseus and Proteus engines as well as the Napier Naiad and Rolls-Royce Derwent. 2 aircraft (RF342/G-36-3/G-APRJ/G-29-1 and RF402/G-APRP) were used extensively for icing trials conducted by Napier Ltd, flying with test aircraft wing sections mounted sail-like on the upper fuselage behind a spray rig. RF342 was used in support of types including the Beverley, Caravelle, Britannia and Comet.
The major user, however, was the Royal Air Force and production Lincoln B. Is were delivered from February 1945. By VE-Day about 50 had been test flown and delivered to maintenance units or to specialist organisations such as the Telecommunications Flying Unit at Defford, the Aircraft Torpedo Development Unit at Gosport, to Rolls-Royce at Hucknall for engine trials and, of course, to Boscombe Down. The Bomber Development Unit at Feltwell received its first Lincolns on 21 May 1945 and the first RAF squadron. No. 57 at East Kirby, received an initial allocation of three Lincoln B. IIs for its Lincoln Trials Flight in August 1945. The B. II was powered by Merlin 66 or 68 engines and was fitted with the Bristol B17 dorsal turret, Boulton Paul ‘D’ rear turret, and Mk IIIG H2S radar.
The surrender of the Japanese and the disbandment of the “Tiger Force” destined for the Pacific, coupled with delays in getting the Lincoln into service, meant that the type was not used operationally during World War II, although it was to see the RAF into the jet era, operating in Malaya and Kenya until it was replaced by the Canberra. The last was withdrawn in 1963. The last operational use of the Avro Lincoln by the Argentenian Air Force in 1967 where after they were retired.
Variants
Avro Type 694
Prototypes to Air Ministry Specification 14/43, three-built
Lincoln I
Long-range bomber version for the RAF. Powered by four 1,750 hp (1,305 kW) Rolls-Royce Merlin 85 inline piston engines.
Lincoln II
Long-range bomber version for the RAF. Powered by four Rolls-Royce Merlin 66, 68A and 300 inline piston engines. Built by Avro, Armstrong-Whitworth and Vickers-Metropolitan
Lincoln III
The Lincoln III was intended to be a maritime reconnaissance, anti-submarine warfare aircraft. The aircraft later became the Avro Shackleton.
Lincoln IV
Lincoln II converted to Merlin 85 power.
Lincoln Mk 15 (B Mk XV)
This designation was given to one aircraft, built by Victory Aircraft in Canada.
Lincoln Mk 30
Long-range bomber version for the RAAF.
Lincoln Mk 30A
Long-range bomber version for the RAAF, fitted with a longer nose and Merlin 102s.
Lincoln Mk 31 (GR 31)
General reconnaissance version of Mk.30 for the RAAF, fitted with a longer nose. Four Rolls-Royce Merlin 85 or 1,650 h.p. Merlin 102 powerplants.
Lincoln MR 31
Anti-submarine warfare/maritime reconnaissance version of Mk 31 for the RAAF.
Avro 695 Lincolnian
Transport derivative similar to the Avro Lancastrian
Lincoln ASR.3.
Initial designation of the Avro Shackleton, which was based on the Lincoln.
Specifications (Lincoln I)
General characteristics
Crew: 7 (pilot, flight engineer/co-pilot, navigator, wireless operator, front gunner/bomb aimer, dorsal and rear gunners)
Length: 78 ft 3½ in (23.86 m)
Wingspan: 120 ft (36.58 m)
Height: 17 ft 3½ in (5.27 m)
Wing area: 1,421 ft² (132.01 m²)
Empty weight: 43,400 lb (19,686 kg)
Loaded weight: 75,000 lb (34,020 kg)
Max. takeoff weight: 82,000 lb [22] (37,195 kg)
Powerplant: 4 × Rolls-Royce Merlin 85 V piston engine, 1,750 hp (1,305 kW) each
Performance
Maximum speed: 319 mph (513 km/h) at 18,800 (5,730 m)
Cruise speed: 215 mph (346 km/h) at 20,000 ft (6,096 m)
Range: 2,930 mi (4,714 km) with maximum bomb-load 1,470 miles (2,365 km)
Service ceiling: 30,500 ft (9,296 m)
Rate of climb: 800 ft/min (245 m/min)
Armament
Guns: 2 × .50 in (12.7 mm) M2 Browning machine guns in nose and tail turrets, and dorsal turret with either twin .50 in machine guns or twin 20 mm Hispano cannon.
Bombs: Up to 14,000 lb (6,400 kg) of bombs [5] (normal maximum). Exceptionally one 22,000 lb (10,000 kg) DP bomb.
