In 2021, a £117 million refurbishment programme to upgrade the fleet to as new condition began; this has included conversion of one first-class carriage to standard class to increase capacity, adding power plugs and new customer information screens.

Following negotiations with several manufacturers, Virgin placed an order with Alstom/Fiat Ferroviaria to produce the envisioned tilting train, which was known by the name Pendolino and was later designated under TOPS as the Class 390.

[11] The purpose of tilt on the Pendolino was to maintain passenger comfort levels when traversing curves at high speed by reducing the sideways forces on the train's occupants, minimising their tendency to slide across the carriage.

[11] Some years after the cancellation of the APT, British Rail had intended to replace the existing fleet of trains on the West Coast Main Line (in conjunction with a planned route modernisation) as part of the InterCity 250 project, but this was cancelled by the government shortly before the privatisation of British Rail during the late 1990s.

Consequently, and in a manner reminiscent of the introduction of the InterCity 225, the lack of signalling upgrades resulted in the maximum line speed being set at 125 mph (200 km/h).

[11] Fiat Ferroviaria supplied much of the content of the Class 390, including the unit's bodyshell and the bogies, while final assembly was carried out at Washwood Heath.

[11] The structure of the Pendolino is largely composed of extruded aluminium panels; allegedly, this material is responsible for the train's exterior surface being considerably smoother than its steel counterparts.

To avoid the risk of striking passing trains or static structures whilst a carriage is being tilted, it necessitates that the body be narrower towards the top than it is at wheel height.

[11] The nose of the Pendolino is manufactured out of composite materials and moulded in a similar fashion as has been used to produce the shells of racing cars.

[11] This construction methodology has been claimed to have been readily compatible with the aerodynamic contouring techniques practised while also retaining considerable structural strength.

To validate its performance, the forward section of the trains was subject to considerable aerodynamic testing to prove its suitability for high-speed operations.

[11] Each of the carriages can tilt up to eight degrees from the vertical; this is done to manage the forces imposed between high speed trains and the track while traversing corners.

This system relies upon trackside beacons, which are typically spaced around 5 miles (8.0 km) from one another, to transmit data to the train; this information, as well as temporarily locking-out the tilting mechanism from being used on relevant stretches of track, also relays the maximum permissible speeds for the adjacent corners.

[11] These systems automatically deliver situational warnings regarding the relevant signals and speed limits to the driver and, if not reacted to appropriately, are able to bring the train to a complete halt.

Reportedly, consideration was given to the adoption of asymmetric window layout during the design process, but this was ultimately discarded in favour of the arrangement used in service instead.

[11] Traction motors are suspended from the underside of the carriage bodies and connected to the driving wheels using a Cardan shaft and transfer gearbox thus lowering the unsprung mass and consequent track wear at high speeds, a feature inherited from its APT ancestor.

Power for each Pendolino is supplied in the form of 25,000 volts AC, and is delivered via the overhead catenary infrastructure installed across its route.

[11] In response to criticisms of the pressure-operated automatic gangway doors fitted to the Mark 3 and Mark 4 carriages (which could easily be held open by items of luggage resting on the floor sensor, allowing draughts into the passenger saloon), the gangway doors of the Pendolino have press buttons instead.

[citation needed] The service introduction of the Pendolino was repeatedly delayed, a fact which has been attributed to the poor project management and the collapse of infrastructure owner Railtrack.

[16] During the Games, they operated a daily return service between the two cities, however, it was not until 27 January 2003 that the first Pendolino carried passengers between London Euston and Manchester Piccadilly.

It was expected that all locomotive-hauled trains would have been replaced by the end of 2004, but the Pendolinos suffered from several technical problems, which granted the Class 87s a temporary reprieve.

[citation needed] Another development during 2004 was the clearing of the units for the North Wales Coast Line from Crewe to Holyhead.

These locomotives have special Dellner coupling adaptors and electrical systems to make them compatible with Pendolino trains, allowing failed units to be rescued quicker.

The entire Pendolino fleet is allocated to Alstom's Manchester Traincare Centre at Longsight, where heavy maintenance is carried out.

Lighter maintenance, cleaning and overnight stabling are carried out at Alstom's other centres: Wembley (London), Oxley (Wolverhampton), Edge Hill (Liverpool) and Polmadie (Glasgow).

[17] The Rail Safety and Standards Board's inquiry into the incident identified a software glitch in the wheel-slip protection (WSP) system whereby the train's friction brakes were inhibited at low speeds after prolonged coasting (such as that occurring on approach to a station).

In September 2006, a Pendolino completed the fastest ever southbound run along the 401 mi (645 km) length of the West Coast Main Line from Glasgow Central to London Euston, at 3 hours and 55 minutes.

The previous record was 4 hours and 14 minutes, set in 1981 by the Pendolino's ancestor, British Rail's Advanced Passenger Train (APT).

On night-time runs between Rugby, Nuneaton and Lichfield Trent Valley, 390002 achieved a record speed for the class of 145.7 mph (234.5 km/h), as witnessed by Modern Railways magazine.

In March 2012, unit 390055 operated a test run on the East Coast Main Line from Edinburgh to London King's Cross.