Chassis
Early chassis types were given a C-series number. When a new lower frame was introduced in 1920 they were known simply by the capacity of the body that was designed to be fitted. From 1925 a sequential letter system was given that ran from A to M, although the M type never went into full production. This was replaced by a new series that used initials to describe the vehicle, such as 'RE' for 'rear engine'.[5]
Different chassis letter codes were used to identify different sizes of petrol engines, but with the introduction of diesel engines from 1933 the size and manufacturer was shown by a suffix to the main code. In this way LD5G denoted an LD with a five-cylinder Gardner engine and FS6B an FS with a six-cylinder Bristol engine, and so on.[5]
All early chassis were used for either single deck buses or goods vehicles. In 1931 a longer J type single deck chassis was offered to exploit the increased length now permissible but this was replaced by the L in 1937. In 1952 by a new Light Saloon was introduced which was built on integral principles. It had no true chassis but lightweight running units were fitted to a special ECW body that gave the bus its strength and rigidity. A more conventional Medium Weight chassis was offered from 1957. A larger single deck, the rear-engined RE, was produced in 1962 and shorter versions to replace the MW appeared in 1968 along with a Lightweight Horizontal engined chassis, to replace the SU midibus and sell to the private sector as a lightweight coach, the LH.[5]
The G was introduced in 1931 as a dedicated double deck chassis, but this was replaced by the K in 1937. Larger versions were offered as laws changed to allow an increase in both width and length, but in 1949 a radically different double deck prototype was tested. This had a specially designed chassis that allowed a conventional body to be fitted within the height of a 'lowbridge' profile, which with a conventional chassis was only possible with gangways below floor level and very restricted headroom inside. This prototype became the Lodekka which remained in production in various forms until 1968. By this time a rear-engine double deck, the VR was available.[5]
The last VRs and LHs were built in 1981 and the last REs in 1982, but production switched to Leyland-badged chassis. These included the B21 and B52 single deck urban bus chassis and the Olympian double deck.
Models
Note that the 'type' shown in the table below refers to the most common configuration. Double deck bus chassis were sometimes given single deck bodies, and bus chassis were often given goods bodies.
Engines
Bristol made their own petrol engines to power their chassis. Until 1929 these were all four-cylinder, but in that year a six-cylinder model was added to the range to power the new C and D models. The C failed to get past the prototype stage, but the D was joined in 1931 by the G and J which also used Bristol's six-cylinder JW engine.
Bristol first offered a diesel-engined chassis in 1933. This was a JO single deck fitted with a Gardner five-cylinder engine. The GO double deck soon followed, but the petrol-engined J and G versions remained in the product range until 1936.[5] Bristol continued to source its diesel engines from Gardner and other suppliers. In 1938 they began to develop their own but a production model was not ready until after World War II. The 8.14-litre AVW engine was available in 1946 and an LSW horizontal version was produced for the LS integral single deck in 1950. Larger 8.9-litre BVW engines appeared in 1957. More than 4,000 diesel engines were eventually produced.
Bodies
Bristol Tramways initially built bus and truck bodies at their Brislington Body Works which was on the same site as the Brislington tram depot. Low demand for new aircraft following World War I saw some bus and lorry bodies built in the aircraft factory at Filton, where the first bus chassis had been built.
Most early Bristol chassis (and some of the few chassis that the company bought from others) had their bodies built by Bristol Tramways, but by the late 1930s most other operators were having bodies for their Bristol chassis built elsewhere.[7] One such outside coach factory was ECW in Lowestoft where they had been building bodies on Bristol chassis for United Automobile Services and other operators since 1929. Bristol Tramways even had a batch of K5Gs bodied by ECW in 1938.
After World War II Bristol's old angular body designs became more like the contemporary, more rounded ECW designs. After nationalisation ECW built bodies for most of Bristol's output.[7] In 1955 it was decided that body production at Brislington would cease. The designs for the HA lorry cab were handed over to Longwell Green Coachworks, a company based near Bristol. All work had been transferred there by 28 May 1956.
Other products
In October 1913 a mobile workshop was built to repair aircraft in the field. A 'large bus body' was equipped with an electric generator which powered a lathe, bandsaw, drills, shaping machine, grindstone and lights. One of the two drills was on a long lead so that it could be used outside the workshop. It was also equipped with work benches, furnace and anvil. It was driven to the Paris Aircraft Show. It was sold to the Royal Naval Air Service in 1914.
More than 1,000 aircraft were built at the Motor Constructional Works to supplement the work of the regular Bristol Aeroplane Company factory at Filton during World War I. Again during World War II Brislington was tasked with manufacturing products to support the war. The fuselages for 1,300 Bristol Beaufighters and 120 Bristol Buckinghams were built and sent to Filton for fitting out. It built gas producer equipment to enable buses and trucks to use anthracite as a fuel. It also produced aircraft and tank components, shells, searchlight generators and other military equipment.
Brislington product's became more diverse after nationalisation. Heavy goods vehicles were designed and built for British Road Services in both rigid eight-wheel and articulated form. A few bus chassis were also fitted out as lorries, as they had done since the earliest days of the factory. A prototype container transporter for British Railways and a light anti-aircraft gun carriage for the Ministry of Defence also made use of BCV's expertise in road vehicle manufacture.
