The AC Locomotive Group

Following abandonment of the APT, new traction was required for the West Coast Main Line to replace the aging first-generation locos. A batch of 50 Class 90 locomotives (an updated version of the Class 87) was built in the late 1980s, generally replacing the remainder of the original fleet.

Beyond the WCML, other main lines were electrified in the 1980s, including the Great Eastern routes to Cambridge and Norwich. For these, some 86s were transferred from their traditional stamping grounds. The East Coast Main Line was also electrified in the late 1980s, and in 1986 a new prototype locomotive, Class 89, 89001, was built, intended for squadron use on the new route. Despite being an undoubted success in trials, and being capable of 125 mph, the requirement for the ECML was changed to 140mph trains, leading to a completely different fleet of locomotives being constructed - the Class 91s, which owed more than a little design to the APT power cars. The deep irony of this change, with hindsight, is that the 91s have never run in service at their 140mph maximum - all ECML services are still restricted to 125mph!

The 89 was to remain a one-off, and because of this it became difficult to maintain and provide spares for. Withdrawn in the early 1990s, it was reinstated after privatisation and resumed duties on the ECML for a few years. It's one-off nature returned to haunt it, however, and it was again out of service by the early 2000s.

The final 3rd-generation AC locomotive design to appear for the national network was the Class 92. This was designed and built in the early 1990s for use on Channel Tunnel traffic, being a dual-voltage, three-system loco capable of taking power from the 25 kV overhead in the UK, Tunnel and France, and from the 3rd rail DC supply in the south of England.

Massively complex, it was several years before they entered full service - only in the early 2000s did full route-availability become standard for the fleet. Sadly, some of the locos have not seen use for many years following the still-birth of the Nightstar international sleeper services; these locomotives are in store.

Beyond the national network another new design appeared in the 1990s. The Eurotunnel Class 9, a Bo-Bo-Bo, single-ended machine designed for exclusive use on Channel Tunnel car and lorry shuttle trains. With a massive 7725hp available these work in pairs at either end of the shuttle trains. In the early 2000s additional Class 9/7s were introduced, with the best part of 9000hp per loco - the earlier Class 9s began to be uprated to match.

With no new electric locomotives on the horizon for the main-line network, could the era of AC electric locomotives be coming to an end? Multiple-unit trains appear to be the fashion for future electric passenger trains, and freight is now predominantly diesel hauled. Only time will tell.