The ten power cars leaving the Virgin fleet in October 2002 were used to boost other fleets and create the Railtrack NMT (43013/014/062).
February 2003 bought about the creation of an entirely new HST sector code and depot: 43013/014/062 were all allocated to the QCAR Network Rail pool based at Derby (DY) for use on the unique High Speed National Measurement Train (NMT). 43013/014 became NR power cars as they were due major exams and could therefore receive all the specialist work whilst being overhauled. 43062 was chosen as it had been ‘blacked’ by Virgin drivers due to constant vibrations in the cab after a derailment at Coventry. It was fitted with a completely new cab and the vibration problems are now history.
The fleet was increased to four with the addition of 43154 in February 2004 (following the discovery of problems with the intended 43101) as a ‘standby’ machine whilst the other power cars received a series of major upgrades. The fleet was reallocated to EC in October 2004, and was supplemented by 43067 joining the fleet during April 2005 to allow further upgrade work to be carried out on the core NMT trio, and this was replaced by 43196 in early 2006. 43154 was returned off lease in November 2005 following the completion of the second upgrade to 43013/014/062 with also included fitting of MTU engines to the three power cars.
In May 2007 a hybrid diesel/battery powered train was first trialled on the Great Central private railway using a specially modified 43089 and a TGS loaded with the Hitachi developed test equipment. 43160 was provided to assist with these trials before joining the FGW fleet, whilst 43089 joined the NMT fleet as their fourth power car after the modifications were removed, although later it left the NMT pool to become a conventional power car once again where it currently resides as part of the East Midlands Trains fleet.