Prototype CRL4
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Notes About This Vehicle

RM1 and RM2 were constructed with AEC mechanical units and bodies built with collaboration between Park Royal Vehicles and London Transport’s Chiswick Works. Delivered slightly out of sequence, RML3 was the last of the four prototypes to arrive, with mechanical units from Leyland (hence ‘RML’) and bodywork from Weymann’s. The fourth numerically was designated CRL4, for Coach Routemaster Leyland, which had bodywork built by Eastern Coachworks.

CRL4 was the first truly bespoke London double-deck luxury coach and was painted in the usual Lincoln Green when received in June 1957. It took to the road on 9th October after a few modifications at Chiswick.

The most noticeable departure from the other three prototypes was the addition of four-leaf folding platform doors. The mechanism for this caused the side blind above it to be moved higher.

Production central area red Routemasters, 27ft 6ins in length, commenced in passenger service in 1959 and 30ft RMLs followed when legislation permitted them. The designation ‘RML’ now standing for RouteMaster Lengthened caused RML3 to be re-classified RM3.

Based on the success of CRL4, a batch of 68 RMCs (RouteMaster Coach) was built and entered service in 1962, this time with Park Royal bodies, a while after CRL4 had been re-classified RMC4 in August 1961.

Benefiting from its forebear, the main batch of RMCs differed in many respects — some subtle, some not. Most noticeably the front was very different. Gone was the side-hinged bulbous bonnet, replaced by the now standard type and larger radiator grille. The RMCs also received stylish twin headlamps as well as the by then standard quarter-drop opening upper deck front windows. Additionally, the separate route number and via points blinds gave way to a single one, not quite as wide as the ultimate destination blind below.

The rear lower deck window configuration was revised and the emergency exit handle moved down. The registration plate by the offside rear was unique to CRL4, but this took a conventional more central position on the RMCs.

Other features of note were the position of the offside rear route number blind on CRL4, which moved farther back on the RMCs to the usual production Routemaster location. CRL4 had no front nearside route number blind under the canopy and the emergency bell push above left of the doors was moved down on the RMCs. Also of note, the fuel tank on the prototypes changed sides on production buses.

Notes About This Drawing

The drawing is based on an undated Chiswick Works general arrangement drawing ‘CR.301.Z.1’. This type of black & white sketch drawing, as implied by the name, is not intended to define detail but as a specification guide to builders.

All the fine detail has been interpreted from several black & white, and few colour photographs, of sufficient quality that could be found and attempts to show the vehicle as closely as possible to how it looked when it entered service. None of the detail can be regarded as definitive.

It should be understood that all four elevations are seen here as one would see each part of the vehicle at a truly perpendicular angle. In real life this is of course impossible.

drawing copyright Douglas Rose March 2018
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