steam train at speed 42

[lokoiutfftty]

why is there nearly always a diesel at the back of mainline steam trains.

i'm from ireland and there has never been a diesel engine at the back of any steam train.

[MrCagivaman]

@lokoiutfftty Because, unlike Ireland, We can''t afford a delay because of a broken down steam loco during the week day period.

[choirboyfromhell1]

And Class 50 at the rear was a nice also...