The Blackburn B-26 Botha was a high wing, twin-engine torpedo and general reconnaissance aircraft designed against Air Ministry Specification M.15/35, a requirement which also produced the Bristol Type 152, later known as the Bristol Beaufort. In the end both aircraft were ordered into production ‘from the drawing board’ in 1936.
Power was provided by two 880hp Bristol Perseus X engines although later aircraft used the 930hp Perseus XA engine (the first aircraft so equipped being Serial No. L6155).
The Botha was of all metal construction and flush riveted throughout. Production took place at both Brough in the East Riding of Yorkshire (382 aircraft) and at a new factory on the north banks of the Clyde at Dunbarton (200 aircraft).
The first B-26 Botha (L6104) was flown for the first time on 26th December 1938 although when tested at A&AEE it was criticised on several grounds, including a lack of longitudinal stability. Additionally it was said to have 'poor elevator control' and a 'high stalling speed' with volumes of exhaust fumes entering the cockpit, plus a number of 'other' issues.
Although the aircraft passed torpedo and mine-dropping tests, its overall poor performance led to a restricted issue to just 4 general reconnaissance squadrons rather than the torpedo bomber units as originally envisaged.
Subsequent production machines featured an increased tailplane area and a larger, aerodynamically-balanced elevator which although it eased the problems it failed to eliminate the wide held opinion that the Botha was 'underpowered and generally unstable'.
The aircraft would carry four crew (pilot, wireless operator, navigator and gunner) and it was armed with a fixed forward firing Vickers machine gun together with two Lewis MkIII guns mounted in a power-operated dorsal turret. Offensive stores also included one 18-inch torpedo, or up to 2,000lb of bombs.
When fully-loaded the aircraft proved to be seriously underpowered at its appointed operational weight and was deemed as having an inadequate single-engine performance in emergencies.
The type eventually entered full operational service with just one Squadron (608 Sqn) based at Thornaby.
It was used for relatively safe North Sea reconnaissance patrols from June to November 1940 after which it was withdrawn from front-line service.
It was subsequently relegated to Training Establishments in support of reconnaissance and bombing / navigation / gunnery training with a few aircraft being used for communications and as target tugs.
At one point The School of General Reconnaissance at Squires Gate, Blackpool had more than 100 Bothas on charge.
Most of the Botha fleet was withdrawn from service and scrapped in 1943 although No 11 Radio School at Hooton Park continued to use the type until April 1944. Their last aircraft (W5073) was not ferried away to be scrapped at Sherburn-in-Elmet until September 1944.
In service, the type was unpopular due to its high accident rate and of the 478 aircraft deployed on training duties, 169 were written off following accidents with 24 of these being ditched at sea following engine failure.
|Powerplants||Two 880hp Bristol Perseus X (or 930hp Perseus XA) engines|
|Span||59 ft 0 in|
|Maximum Weight||17,628 lb (Perseus X), 18,450 lb (Perseus XA)|
|Capacity and armament||Four crew; One forward-firing Vickers gun, two Lewis guns in dorsal turret. One 18 inch torpedo or up to 2,000 lb bombs.|
|Maximum Speed||220 mph at 15,000 ft (Perseus XA)|
Total of 580 aircraft (all Botha Mk I), production split between Brough (380) and Dumbarton (200).
No examples of the Blackburn B-26 Botha survive, most aircraft having been scrapped in 1943.