In mid-1984, TS Sc48204 was withdrawn from Set 370 004 and was sent to the Engineering Development Unit (EDU) at Derby RTC for conversion to an APT-U test vehicle, with extensive rebuilding of the underframe being undertaken in order to incorporate tilting double bogies based on the BT12 units.

Following the completion of the vehicle some static testing was undertaken at Derby, as well as dynamic testing on the West Coast Mainline in an APT formation, where the coach was inserted between the TBF and NDM vehicles. The APT-U project evolved into the IC140 project which, once tilt was dropped from the specifications, became the IC225 Class 91/Mk IV rollout on the East Coast Mainline.Renumbered as 977527 in Departmental use, the coach seems to have retained 48204 while testing, the number being painted out once it had been withdrawn from the APT dynamic testing some time during mid-1989. Stored at the RTC yard in Derby, the vehicle was finally scrapped in October 1989.

• Length - 27.6cm, Width - 3.5cm, Height - 5cm
• 1:76 Scale 00 Gauge
• Painted Finish
• Minimum Curve (mm): Radius 2
• Number of Parts: 1