Test Trains

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Network Rail's Infrastructure Monitoring trains (or 'Test Trains') are operated on their behalf by Colas Rail, but some use Class 37 locos hired in from DRS and Class 67 locos from DB Schenker. Colas took over from DB Schenker on 7th September 2015. Until 2010 these test trains were operated by Serco.

NMT - New Measurement Train

Further details about the NMT can be found on the HST page.

43013 and 43014 pass new point work at Slateford on 24/02/2009. Photo by calderdepot


TRC - Track Recording Coach

This is a Mk2 type coach and can be formed in a loco-hauled formation as a substitute for the NMT, and for a time ran in the NMT set until the MK3 test coaches were ready for use.

Numbered 999550. It has thin blue waist stripes as per NMT stock.


PLPR - Plain Line Pattern Recognition


37423 at Cradlehall » DRS 37423 is seen leaving Inverness at Cradlehall working 133Y 1452 Inverness Millburn C. Rail - Mossend Down Yard. 37419 was on the front. Photo by JONATHAN-BROOKS




TRU - Track Recording Unit


A purpose built 2-coach DMU based on the Class 150/1 sprinter.

Vehicles are numbered 999600 & 999601, and carry the set number 950001.

950001, 2Q08 approaches Prestonpans. February 2nd, 2010 Photo by KeithSanders



TIC - Track Inspection Coach


This is a Mk1 type coach (orignally an inspection saloon), with part recessed bodsides. It was used when the TRU was unavailable.
Numbered 999508
37069 and 37259 top and tail with the TIC on the Lanark branch in 2007 Photo by jackprentice2007



Radio Survey Train


Former Mk2E TSO coaches, with various low-profile radio antenna on the roof.

Used for testing the NRN, CSR and GSM-R systems.

Previously, a former class 101 DMU set known as Iris II was used on this duty.

1Q20 heading home » 31602 on Mossend-Derby crosses the Clyde at Crawford 29/05/09. This train has 2 radio survey coaches in the formation Photo by 61600



UTU - Ultrasonic Test Unit


The Ultrasonic test coaches were converted from Mk1 EMU motor coaches. They are noticable at night by the bright lighting around the equipment fitted bogie.

There are currently three trains, each with one of 999602, 999605, 999606.

31105, with a UTU train, March 2009 Photo by jackprentice2007


SGT - Structure Gauging Train


Sometimes referred to as OSG - Optical Structure Gauging.

Features the 'Optical Car', a 2-axle wagon, painted black numbered DC 460000 .

31459 cerberus and 31285 on the Structure Gauging Train stabled in front of Carlisle signal box, June 2008 Photo by pedro12



MENTOR - Overhead Line Equipment Testing


Numbered 975091. A Mk1 coach with a flat roof and a pantograph.

37069 Leads Test coach Mentor & 37612 on 1Q18 at Hillington East, March 2009 Photo by JimGillies


Other Vehicles


The individual test coaches may be accompanied by other vehicles, for staff accommodation, power supply generation or additional brake force.

From 2008, former DBSO driving trailers have been converted for use on the test trains.

See Also

External links