From HSTs to IETs

The face of the Great Western Main Line is changing. New 125mph bi-mode Intercity Express Trains are taking over more and more services previously operated by the veteran High Speed Trains introduced in the 1970s.

The HST power cars were fitted with MTU engines in 2005-08 to improve reliability, but a long-term solution was still needed.

The ‘Sparks Effect’ announced in 2009 ( RAIL 624) followed Government’s announcement for the Intercity Express Programme ( RAIL 609). Wires would be strung up to Bristol and Swansea, with new bi-mode trains travelling on the GWML. The deal for the trains was eventually placed with Agility Trains in 2012, and deliveries began in March 2015 ( RAIL 771).

Meanwhile, the GWML infrastructure upgrade was unravelling. Planned testing west of Reading was not possible due to the late delivery of overhead line electrification that delayed driver training.

By mid-October 2017, when IET was due to enter traffic, the wires were only energised as far as Twyford (it should have been Bristol). By May 21 this year, the work had reached Didcot Parkway.

The ambition is Swindon by the summer, and while Cardiff was the plan for the end of the year, it is now more than likely it will be the end of Control Period 5 (March 31 2019).

All of which means that the IEP order had to change. The original deal was for 36 five-car bi-modes and 21 nine-car electric multiple units. The latter were converted to BMUs before delivery, and now GWR has 57 Class 800s on order.

As at the end of May, 33 five-cars had been delivered, with 32 in traffic. Five nine-car sets had been delivered, with one accepted although not in use. This is behind schedule, with faults being evaluated and cured as they’re found.

Two ‘800/ 0s’ are used to test modifications (800003/ 004), while a further two per day are being used for driver training to Plymouth and Penzance ahead of the introduction of the almost identical Class 802s from (it is expected) July.