Glossary of United Kingdom Railway Terms - T

T

• Tadpole: 3R DEMUs. Named due to having two vehicles 8 ft 2½ in wide and one vehicle 9 ft 3 in wide.

• Teddy Bear: British Rail Class 14 diesel-hydraulic locomotives for shunting and trip-working. Coined by Swindon Works' foreman George Cole who quipped "We've built the Great Bear, now we're going to build a Teddy Bear!".

• Thousands: Class 52 diesel-hydraulic locomotives (the "Westerns") given the number range beginning with D1000.

• Thumper: Southern DEMU (BR Classes 201 – 207) – unlike conventional DMUs these used a single, comparatively large diesel engine and electric generator mounted immediately behind one driving cab. The power units made a distinctive "thumping" noise when working hard.

• Thunderbird: a locomotive kept on standby at a strategic location, ready to rescue a failed train. (From Thunderbirds)

• Tractor: British Rail Class 37 diesel-electric locomotive, possibly from the engine sound, also because they could be found hauling almost anything as a mixed-traffic design.