Originating in 1944, the Bristol Type 170 was intended for military use, being designed as a utility transport capable of airlifting the standard British Army 3-ton truck. However, it arrived a little late for WWII, and instead became Bristol's first post-war production model. Two prototypes were ordered by the British Ministry of Supply, with the proviso that Bristol build two more. The result was several variants, the cargo Mk.1 Freighter with clamshell nose-doors and the solid nosed passenger Mk.II Wayfarer. The first of two Mk.1 Freighter prototypes (c/n 12730 G-AGPV) was flown on December 2, 1945. Interestingly this aircraft was basically a shell and did not have nose doors. The first of the Mk.II prototypes (c/n 12731 G-AGVB) followed on April 30, 1946.

The Mk1A was a mixed traffic version, while the Mk.IB, Mk.IC, and Mk.ID were built for specific customers (BEA and BSAA). Mk.II variants were the IIA with pantry, the Mk.IIB built for BEA, and Mk.IIC with seating forward of the spar and a baggage hold behind. Service trials resulted in the production of the Mk.21 with an increase to the wingspan of 3.05m (10 feet) and a change from the 1,690 hp Hercules 630 engine to the Hercules 634. Structural failure of the fin had occured to two Mk.21s during single engine climb (in 1949 over the English Channel and in 1950 at Llandow) and this lead to a redesign. The Mk.21E was a convertible cargo/passenger with some heating and soundproofing. Further development lead to the Mk.31 again with engines uprated to the 1,980 hp Hercules 734 and a dorsal fillet. This was also produced as the Mk.31E in similar configuration to the Mk.21E, and the Mk.31M a military version which was set up for supply dropping. Final variant was the Mk.32 with a fuselage stretch of 1,52m (5 feet) giving a distinctive 'droop' nose. Built for Silver City Airways this allowed for up to three cars and 21 passengers to be carried on their English Channel 'airbridge' service. Conversion of the Mk.32 to a 'Super-Wayfarer' version was capable of carrying 60 passengers. Plans to develop the type 179 with a twin boom configuration and the Type 216 powered by RR Dart turboprops did not proceed.

The B170 was versatile and popular - capable of carrying a 6,135kg (13,500lb) payload, up to 20 passengers, or three cars. Production amounted to 214 aircraft in the various versions being built between 1945 and 1958 either at Filton or Weston-Super-Mare. The aircraft were utilised by several air forces including the RAF (19), Argentina (14), Australia (4), Canada (6), and Pakistan (38), as well as commercial operators around the world.

Accommodation : 2-3 Crew (12-20 Passengers)
Dimensions
Span : 32.92m (108'0ft)
Length : 20.83m (68'4ft)
Height : 6.56m (21'6ft)
Weight
empty : 12,380kg (27,229lb)
max : 20909kg (46000lb)
Power Plant : 2x 1980hp Bristol Hercules 735
Performance :
max speed : 368km/h (230mph)
max climb : ft/min (m/min)
ceiling : ft (m)
range : km (miles)