When it was issued Air Ministry Specification 5/24 sought an advanced trainer for Royal Air Force use alongside being suitable for the Fleet Air Arm for practice deck-landings and general seaplane operations. This resulted in primary characteristics which included good low-speed handling and good acceleration on take-off.
Contracts were placed for three prototypes; Blackburn TR1 Sprat (N207), Vickers Vendace I (N208) and the Parnall Perch (N217). Power in each case was provided by a 275 hp Rolls-Royce Falcon III engine although the Sprat could also accommodate the Siddeley Puma or ADC Nimbus engines.
The Blackburn Sprat was a single-bay biplane with folding wings and a wide-track divided undercarriage. Unusually, the centre section struts were in an 'X-configuration' splayed out from the fuselage top longerons, reminiscent of the earlier Blackburn Dart and Velos. The air crew were provided with triangular windshields with flight instruments arranged along the trailing edge of the upper wing centre section.
Twin floats were fitted for seaplane operations and the types water handling was said to be excellent. Correctly trimmed, the aircraft would fly cleanly off the water surface, even with the pilot’s hands off the controls.
The prototype (N207) was flown for the first time on 24th April 1926 and was subsequently tested at Martlesham Heath (on wheels) as well as Felixstowe (on floats) during June 1926.
By 3rd July 1926, N207 had been restored to its landplane configuration and was shown in the New Types Park at the annual RAF Display at Hendon. It gave a well-received and spirited flying display at the show although sadly it did not receive any order nor a production contract.
The winning design was judged to be the Vickers Vendace 1 although also failed to receive a production contract as the requirement was later cancelled as on economy grounds.
Variants & Numbers Built
One prototype only, serial number N207.
|Powerplant||One 275 hp Rolls-Royce Falcon III|
|Span||34 ft 9 in|
|Maximum Weight||3,220 lb||3,550 lb|
|Capacity & Armament||Instructor and student; no armament|
|Speed (sea level)||115 mph||112 mph|
|Speed (5,000 ft)||112 mph||109 mph|
Nil, presumed scrapped in 1926.