Re: Brecon Mtn Railway track extension, 1st day running to Torpantau

Another consideration with operating steam through tunnels - is there a grade? If so, drifting the locomotive on the down grade will lessen the stack discharge. Of course the return trip will encounter the grade. If the grade goes all the way through the tunnel, the engine will be working harder in one direction. If the grade crowns inside the tunnel the engine can work up to speed then ease through the bore using momentum to take the train up to and over the high spot to drift down the other side. The crew would have to control the slack action which increases with the length of the consist.

Since the tunnel was built for standard gauge there will be extra clearance which helps lessen the smoke "crowding" the train.

Stewart



Edited 1 time(s). Last edit at 04/09/2014 05:21AM by Stewart Rhine.