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The Daimler Roadliner was a single deck bus or coach chassis built by Daimler between 1962 and 1972. Notoriously unreliable, it topped the 1993 poll by readers of ''Classic Bus''〔classicbusmag.co.uk〕 as the worst bus type ever, beating the Guy Wulfrunian into second place. It was very technologically advanced, offering step-free access twenty years before other single deckers; as a coach, it was felt by industry commentators to be in advance of contemporary UK designs. ==Background and prototypes== In 1960 Transport Vehicles (Daimler) Ltd, The Commercial Vehicle subsidiary of Daimler Company Ltd, launched its Fleetline double decker at the Earls Court Commercial Motor show, this was the second British type of rear engined double decker. Its major advantage over the Leyland Atlantean was that its patented concentric-drive gearbox enabled fitment as standard of a dropped-centre rear axle, allowing a body suitable for low bridges of high to have a centre-gangway seating plan for the full length of both decks. In comparison the low height Atlantean needed an awkward side-gangway abaft upstairs to allow legal internal headroom throughout. The standard power unit for the Fleetline was the 150 bhp Gardner 6LX which was the most economical diesel engine in its class, and regarded by many engineers as even more reliable than the Leyland O.600. By the end of 1962 125 Fleetlines had been delivered and over 300 were on order. This pleased Daimler's new owner Jaguar Cars Ltd and Jaguar’s MD Sir William Lyons allowed work to start in mid-1962 on a new single decker chassis to replace the underfloor engined Daimler Freeline. Two chassis, numbers 36000 and 36001 (model SRD6) were constructed to the newly allowed maximum dimensions of long and wide, they featured an identical drive layout to the Fleetline and shared with it a transverse rear engine location. However, the power unit for these prototypes was a horizontal Daimler CD6 engine fitted with a turbocharger and arranged in the rear nearside corner of the chassis so that all ancillaries could be accessed from the engine's upper face. The radiator was mounted at the front and the chassis had conventional steel leaf springs. Chassis 36000 was shown on the Daimler stand at the 1962 Commercial Motor show and a brochure was produced for the type, although production was not an immediate prospect as the Daimler engine had ceased production. Customer interest in a modern Daimler single decker was however strong enough for Lyons to give the go ahead for a production bus of this type. Instead of the complex transverse horizontal drive it was decided to use a vertical longitudinal rear-engined layout, Instead of the very low horizontal frame of the first two chassis, this was slightly higher at the front and ramped gently upward and tapered outward toward the rear, where the Cummins VIM V6-200 engine was mounted. This 9.6-litre 90-degree vee-six engine developed 192 bhp at 2600rpm and was compact enough to fit under the rear seat on a bodied bus and allow drive to pass through a conventional Daimler SCG Daimatic four-speed semi-automatic gearbox to a straight spiral-bevel rear axle manufactured by Eaton, an electrically operated two-speed axle being optional. All round air suspension was standard, with rubber and steel leaf options. Although some drawings show a front-mounted radiator, standard production versions had this mounted on the rear offside, as on the Fleetline. Other components such as the front axle, steering, brakes, driving controls etc. were similar to those of the Fleetline. The model was announced as the Roadliner model SRC6-36, this was the third and last Daimler bus chassis to be given a model name as well as an alphanumeric code. Left hand drive chassis 36004 and Duple Coachbuilders 51 seat coach demonstrator CWK641C on chassis 36005 were shown at the 1964 show together with the first example sold to an operator, 6000EH of Potteries Motor Traction (chassis 36003). The PMT bus had a 50-seat Marshall body to BET style, featuring no steps and a slightly ramped floor up to the rear bench. The floor level was so low side-facing bench seats had to be fitted over both sets of wheelarches, a contemporary reviewer remarked the footstools to the front benches as rather high. This bus entered service in late 1964 as number SN1000 and unprecedentedly the union branch operating it were so impressed they sent a letter of congratulation to Daimler. The coach, and a further Marshall bus CVC124C on chassis 36002 started work from early 1965 as Daimler demonstrators, the coach in particular garnering a great deal of praise on its road tests. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Daimler Roadliner」の詳細全文を読む スポンサード リンク
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