BR CLASS 150/0 - EX SILVERLINK LONDPN OVERGROUND-The British Rail Class 150 Sprinter is a class of d
0BR CLASS 150/0 - EX SILVERLINK LONDPN OVERGROUNDThe British Rail Class 150 Sprinter is a class of diesel multiple-unit passenger trains developed and constructed by BREL York between 1984 and 1987 for use on regional services across the UK. The type is a second-generation design, built to more modern standards and based on BR's Mark 3 body design for longer-distance services. It was developed alongside the lower-cost "Pacers", which were built using bus parts, for use on short-distance services.[10] Two prototype units were built followed by 135 production units in two batches. Subsequently, further members of the Sprinter family were also developed and introduced to service, including the Class 153, Class 155, Class 156, Class 158, and Class 159. The type remains in service as of 2021. By the beginning of the 1980s, British Rail (BR) operated a large fleet of first generation DMUs, which had been constructed in prior decades to various designs.[10] While formulating its long term strategy for this sector of its operations, British Rail planners recognised that there would be considerable costs incurred by undertaking refurbishment programmes necessary for the continued use of these aging multiple units, particularly due to the necessity of handling and removing hazardous materials such as asbestos. In light of the high costs involved in retention, planners examined the prospects for the development and introduction of a new generation of DMUs to succeed the first generation.[11]In the concept stage, two separate approaches were devised, one involving a so-called railbus that prioritised the minimisation of both initial (procurement) and ongoing (maintenance & operational) costs, while the second was a more substantial DMU that could deliver superior performance than the existing fleet, particularly when it came to long distance services.[11] The initial specification developed for the latter type was relatively ambitious for the era, calling for a maximum speed of 90 MPH (145 km/h), a rate of acceleration compatible to contemporary EMUs, the ability to couple/work in multiple with existing EMUs, facilitate through-access for passengers, feature pressure ventilation, the ability to assist another failed unit, and to comprise either a three or four-car consist.[11]This specification led to the development of the experimental British Rail Class 210 DMU. However, to deliver the performance specified, it was found that relatively expensive equipment had to be used, particularly to provide sufficient speed, acceleration, and through-passenger access; it also had maintainability problems due to space limitations. Despite these shortcomings, it was recognised that a production fleet that was assembled from proven components would possess both a greater reliability level and lower maintenance costs; it was forecast to achieve an availability rate of 85 percent.[11] As such, the type had sufficiently demonstrated a promising reduction in maintenance costs was achievable, especially once initial teething problems were dealt with, as well as the wider value represented by a new generation of DMUs in the reduction of ongoing costs for BR.[11]By 1983, experiences with the Class 210 had influenced planners to favour the procurement of a new generation of DMUs, but to also adopt a new set of specifications that were somewhat less demanding than the prior set.[11] Specifically, it was decided to drop the top speed from 90 MPH to 75 MPH, as testing had revealed the higher rate to deliver no perceivable improvement in journey times due to the typically short spacing of the stations the type was intended to serve. Furthermore, it was determined that a propulsion system deliver