Saro Lerwick
The Saro Lerwick was a British twin-engined maritime patrol flying boat built by Saunders-Roe for RAF Coastal Command. Ordered off the drawing board to Air Ministry Specification R.1/36, it first flew in 1938 but proved unstable both in the air and on the water, and only 21 were built. It served mainly with No. 209 Squadron from 1940, was withdrawn from front-line service in 1941 as Catalinas arrived, and the survivors were scrapped by early 1943.
Why It Mattered
The Lerwick was Saunders-Roe's response to Air Ministry Specification R.1/36, which called for a medium-range boat to fly anti-submarine patrols, escort convoys and carry out reconnaissance. It was meant to serve alongside the Short Sunderland in Coastal Command, replacing the RAF's ageing biplane flying boats such as the Saro London and the Supermarine Stranraer. The contract was issued in June 1937, before any Lerwick had flown: the type was ordered straight off the drawing board, with no prototype built first. Its failure then hurt the RAF directly, for as History of War records, Sunderland production had been scaled down in expectation of the new aircraft, and the result was a desperate shortage of flying boats in 1940. History of War ranks it among the least successful aircraft the RAF operated in the Second World War.
Design Notes
The Lerwick was a compact, all-metal, twin-engined high-wing monoplane. Its hull followed conventional flying-boat practice, with a planing bottom, and a stabilising float was carried beneath each wing on long struts. Two Bristol Hercules radial engines of 1,375 hp each provided the power. The 2,000 lb bomb load was carried within the engine nacelles, and the defensive armament sat in three powered turrets: a single Vickers K gun in the retractable nose turret, two Brownings in a dorsal turret and four guns in the tail turret. As development went on the crew rose from six to nine, and the aircraft finished significantly heavier than the specification allowed. Flight testing found it unstable in every axis, so that hands-off flight was impossible, and it was just as unsteady on the water, needing far too much room to take off. Saunders-Roe tried auxiliary fins and an extended rudder and finally fitted a much larger fin, but the changes brought only a minor improvement, and the type kept what Wikipedia calls its vicious stall.
Operational History
The first Lerwick made its maiden flight in October 1938. In the summer of 1939, four Lerwicks were delivered to No. 240 Squadron to replace its Saro Londons, but in October the squadron stopped flying them, and on 24 October the entire programme was suspended. The programme was reactivated on 1 November 1939, and in December No. 209 Squadron at Oban received its first aircraft; the type entered service with that squadron in 1940, replacing Supermarine Stranraers. Losses began almost immediately: on 20 February 1940 the first aircraft was lost when a wing float collapsed as it landed, and in June a second aircraft was lost in the same way. In the summer of 1940 the squadron moved to Pembroke Dock, but the Lerwick had to be grounded for more modifications, and with that went any chance of a part in the Battle of the Atlantic. Across its front-line career, Lerwicks attacked U-boats on only two occasions, and neither submarine was damaged. In April 1941, No. 209 Squadron began receiving American Catalinas; the last of the 21 Lerwicks was delivered in May, and that month the type was withdrawn from front-line service. Most of the remaining aircraft were transferred to No. 4 (Coastal) Operational Training Unit at Invergordon, where more were lost in accidents. The Lerwick returned briefly in mid-1942 for operational training with the Royal Canadian Air Force's Nos. 422 and 423 Squadrons at Lough Erne, and the surviving aircraft were retired at the end of October 1942.
Afterlife
By the end of 1942 the Lerwick had been declared obsolete, and by early 1943 the survivors had been scrapped. The type's losses sum up its career: eleven of the 21 built were lost or written off in three years of operational service, ten of them to accidents and one for an unknown reason. No Lerwick survives today. What remains is the lesson: History of War presents the Lerwick as a warning against ordering a new design straight off the drawing board.