• Class: BR Class 28
  • Number: D5705 (formerly), D5 (currently)
  • Designer: Metropolitan Vickers
  • Builder: Bowesfield Works
  • Configuration: Co-Bo

D5705, also later known as D5, is BoCo's brother, who was only mentioned in an annual. In another annual, BoCo claimed to have a vigintuplet brother named "CoBo" in order to play a trick on Bill and Ben. D5705 is in fact a real diesel engine preserved and under restoration at the East Lancashire Railway. Not only that, but he pretends to be BoCo at Day Out with Thomas events.


D5705 survived by historical accident as a technical services engine and then carriage heating unit TDB968006 before being preserved in 1980. The Class 15 Preservation Society has signed an agreement with the owners of D5705 to become its custodians during its restoration and operation for the next ten years, although funding will remain separate.


D5705 is painted in British Railways Brunswick Green livery with yellow warning panels.


The Railway Series

Companion Volumes

Annual Stories


Other Railways
87546 and 98462Workshop EnginesThe Foreign EnginesDieselThe Foreign EngineThe Derailed EngineJinty and PugThe DieselScrapped EnginesD199Gordon's BrothersBritish Railways DieselsKing James IOld Stuck-UpAlfred and JudyToby's Brothers87831020The Highland EnginesThe Diesel Shunter3112010751WilbertSixteenSixteen's FriendsAlbertBahamasD5705LembergPretty PollyThe DukedogsBritish Railways
LadySpencerHiroHiro's FriendsConnorCaitlinStephen's CompetitorsThe Mainland EnginesGatorSamson
AshimaRajivYong BaoVinnieCarlosRaulShaneEtienneFriedaGinaAxelIvan
Silver JubileeHelena
Spencer's Special CoachesConnor's CoachesCaitlin's Coaches
The Flying ThistleThirteenThe High-Speed Post Train