BL1, BL2 and BL3

BL1 dragging a metrocar

BL3 alongside the Gosforth top shed

BL1, BL2 and BL3 (numbered 97901, 97902 and 97903 respectively in TOPS) are three 0-4-0 battery-electric/wire-electric locomotives manufactured by the Hunslet Engine Company in 1988. They were purchased as new by Nexus, who own them to this day, for non-passenger use on the Metro network.

Technical specifications

They each weigh 26.25 tonnes (tare), have a maximum speed of 55 km/h (only 50 km/h permitted), and measure to 7500mm × 2600mm × 3555mm (including the buffers and the lowered pantograph). They use Westcode electro-pneumatic brakes, single pipe automatic air brakes, and pneumatic parking brakes to clamp disc brakes. They are fitted with both screw couplers and BSI automatic couplers. They use a 270-cell, 540V, 216Ah lead acid battery, as well as a 110V, 28Ah lead acid auxiliary battery. They use a traction motor rated at 180 HP and 830 r/min. They use compressors which supply air at 10 bar and 32cfm to two reservoirs holding 2.4cf of air each.

They have a single cab, positioned on the 'B' end of each locomotive. The cab contains a swivel chair and two desks to allow for driving in either direction.

Usage

Any number (one, two or three) of BLs can be used together in a train, either coupled together or top-and-tailing, with a trailing load of 85 tonnes permitted per BL, allowing for a trailing load of up to 255 tonnes when all three BLs are used. A BL can haul a coupled metrocar and be driven either from the BL or the metrocar. A metrocar can also haul a coupled BL, but it must be driven from the metrocar because driving the BL in this configuration puts too much strain on the auxiliary battery.

The BLs have historically been used for a variety of purposes, including depot shunting, rescuing failed metrocars, and providing traction to unpowered vehicles such as wagons (including the Rail Head Treatment Train). They are approved to operate on Network Rail infrastructure, although they have very rarely been used there. However, they are no longer considered fit for purpose. BL2 and BL3 are now believed to be fully withdrawn, and BL1 sees very little use outside of Gosforth Depot, with the last two known uses outside of the depot being driver training and over 5 months apart (13 August 2025 and 26 January 2026). Traction outside of the depot, including for rescues and wagons, is now typically only provided by the passenger stock (metrocars and Class 555 units) and MA60.

Planned refurbishment

On 24 April 2026, Nexus published a preliminary market engagement notice in preparation for tendering for the refurbishment of all three BLs at an estimated cost of £1-2 million. The refurbishment will encompass:

• Modernisation of the traction equipment (motor alternator and motor generator set) using solid‑state power technology and power electronics.
• Overhaul of structural components, suspension, wheelsets, and key mechanical assemblies.
• Renewal of high voltage and auxiliary electrical systems.
• Upgraded control equipment.
• Readiness for future signalling integration.
• Refurbishment and commissioning of brake discs and brake system.
• Improvements to the cab environment (sealing, comfort, ergonomics).

BL3 plaque

BL3 features a plaque on its exterior reading

Lewis Potts
Metro Engineer
from 1975 to 2016