>>1982892The Warships were all withdrawn before BR adopted the TOPS system, so they never received TOPS numbers. The power cars for the prototype HST were designated class 41, but when the HST was reclassified as a multiple unit, the power cars were given coach numbers, those being 43000 & 43001. The first "production" HST power car was then numbered 43002, and since there was no TOPS entry for class 43 locomotives, they could be allocated that class number going forward