18 April 2009

How Voyagers & Class 90s will fair

New contributor 'DB' compares the three traction types in service with Virgin Trains - two of which on a temporary basis to cover for the damaged Pendolino. He opines that suitable replacement stock has been sought to maintain punctuality by attaining the top line speed and acceleration needed on one of the UK's busiest rail lines, even though they may not be to passengers' tastes.

The Class 390 Pendolinos utilised by Virgin Trains are only permitted the top West Coast Main Line (WCML) speed of 125mph when their tilt systems are fully operational; otherwise only the nominal 110mph is allowed. The higher speeds are so-called Enhanced Permissible Speeds or EPS for short.

Rugby was the cause of one of the most significant bottlenecks on the WCML, though, as a whole, much remodelling has taken place in this area, which has seen the ability of the Pendolinos to run at their maximum 125mph be increased significantly. I think the impact of a few Class 90-hauled trains with Mk3 carriages, with their lower maximum speed of 110mph, won't have much of an effect on Virgin Trains' Very High Frequency timetable.

Why? Class 90 acceleration is top class - better than an Class 43 high-speed train (Intercity 125) when hauling 8 or 9 coaches. The WCML's top line speed of 125mph is only permissible for Pendolinos and Class 221 Super Voyagers when their tilting mechanisms are working. Nothing else. Non-'super' Voyagers (Class 220s) are the lighter but non-tilting variant and are prevented from travelling above 110mph. In terms of speed and acceleration the Class 221s acquit themselves fairly well alongside the Pendolinos, even at a slightly lesser speed. (DB)

Further reading can be obtained by visiting the Railway Performance Society's website.

Click here to learn more about Virgin Train's Very High Frequency timetable.