Class 150 & 156 Automatic Sanding Modification Upgrade

Following the publication of the RAIB report 12/2023 into the Salisbury Tunnel Junction

collision of October 2021 and subsequent conclusions, there is direct recommendation to

install automatic sanding equipment on all fleets. As such Northern is looking to develop

automatic sanding modification on Northern's Cl.150 and Cl.156 fleets.

NTL have assessed our fleet and this notice is to direct award an agreement which will see a

modification to the already installed WSP system to permit automatic sanding on cl.150 and

cl.156 units (qty 288 vehicles all DMS/DMSL).

With the exception of Northern's Cl.150 & CL.156 fleets, all fleets are installed with

automatic sanding systems that deposit sand onto the railhead under the third axle at a fixed

rate, triggered immediately when a unit encounters low adhesion. Where as the 15x fleets are

fitted with Single Fixed Rate Sanding systems which further inadequacies of standard SFRS

systems were highlighted after the Salisbury collision.

The project scope is to:

• Modify already fitted SFRS system as to enable automatic sanding across the Class 150s

& 156s

o Which will improve and standardise sanding response time once a unit has encountered

low adhesion conditions and remove the human element.

• The modification is planned to have as many units completed before leaf fall 2025 on all

Northern Cl.150 and Cl.156 units as to mitigate the risk of further incidents moving forward.