The Bristol Aeroplane Company Type 148 was designed against Specification A.39/34 for an Army co-operation monoplane. The Bristol Type 148 design was heavily based on the Bristol Type 146 single-seal fighter, differing in having two crew seated in tandem, the rear occupant having a defensive Lewis gun.
The 39ft span tapered wing seen on the Bristol Type 146 was replaced by a constant chord wing of 40ft span with 25% greater wing area. The fixed, forward-firing, eight-gun armament was reduced to two guns in the port wing of the Bristol Type 148.
The design incorporated a bomb-aiming position in the fuselage floor and this could be accessed from the rear cockpit with the bombs being carried on under-wing racks.
Two prototypes were ordered (K6551 and K6552). The first was powered by a Bristol Mercury IX engine, whereas the second was fitted with a Bristol Taurus engine and this aircraft was designated as the Bristol Type 148B.
The first prototype flew for the first time on 15th October 1937, and demonstrated a wide speed range (from 62 mph to 255 mph), despite the planned automatic slots not yet having been fitted. Although service trials found the design generally acceptable, the high wing configuration of the Westland Lysander was preferred.
The first prototype was unfortunately damaged, following failure of the undercarriage to lock down. It was subsequently repaired, after which it was fitted with 905 hp Bristol Perseus XII power unit for engine endurance testing.
The Bristol Type 148B (K655), fitted with a 1,050 hp Bristol Taurus II engine, was first flown in May 1938, being used thereafter for Bristol Taurus engine test and development work.
|Bristol Type 148||Bristol Type 148B|
|Powerplant||One 840 hp Bristol Mercury IX radial engine||One 1,050 hp Bristol Taurus II radial engine|
|Span||40 ft 0 in|
|Maximum Weight||5,250 lb|
|Capacity and armament||Two crew: pilot and bomb aimer / gunner. Two forward firing 0.303 Browning machine guns and one defensive 0,303 Lewis gun. Provision for under-wing bomb carriage.|
|Maximum Speed||255 mph||290 mph|
|Bristol Type 148||One only K6551: initially Mercury IX powered; then Perseus XII|
|Bristol Type 148B||One only K6552: powered by Taurus II engine|