When the first double deck bus took to the streets of Britain a great hurdle for the manufacturers came with it, the overall height.
The main obstacle where the vehicle was concerned was the rear axle. The lower deck floor obviously had to cover this resulting in quite a distance from ground level. Adequate headroom within the saloon was also desirable both upstairs and downstairs. For quite some time a vehicle height of around 14 to 15 feet was the result.
One novel solution was to provide a lower ceiling on the upper saloon, leaving enough room for seated passengers. A sunken gangway was provided along one side, this encroached into the lower saloon. The seats on the upper saloon of this 'lowbridge' design were of the bench type intended to accomodate four passengers. Vehicle heights were then drastically reduced to as little as around 13 feet.
Bristol's designers worked for many years to overcome the height issue from a vehicle chassis point of view. In 1949 the first of two prototype vehicles was constructed. The transmission on the vehicle was mounted along one side of the chassis and the rear axle was of a drop centre design. This then allowed a much lower floor in the lower deck and a conventional layout on the upper deck with an overall height of approximately 13 feet 6 inches. The LD was born and aptly named Lodekka by Bristol. After numerous modifications the LD went into production in 1954 enabling the ending of K Type production. Indeed the vehicle was viewed with great envy by non nationalised concerns. A licence agreement with Dennis saw the Lodekka freely available as the Dennis Loline (shame about the mechanical biscuit tins they build these days!). A change in vehicle regulations saw an increased length of 30 feet permitted, the LD became available as the LDL (Long Lodekka) and a 27 feet long LDS (short Lodekka) version.
At about this time the vehicle entrance/exit began to appear towards the front of the bus. In 1960 Bristol launched a new range of flat floor Lodekkas (the lower saloon floor had a slight central gangway on the LD range), FS Flat floor Short (open rear platform), FSF Flat floor Short Forward entrance, FL Flat floor Long (open rear platform), FLF Flat floor Long Forward entrance. These codes would then be followed by the engine code (number of cylinders and make). 5 cylinder Gardner (5G), 6 cylinder Gardner (6G) or Bristol's own BVW engine (6B) were all available, so now you know what FLF6G means! In 1962 the FSF and FL variants were discontinued as operators preferred the other two variants.
Click HERE to view some Lodekkas.