Wait patienly until another engine / train arrives!!
A friend was stuck for 6 hrs+ on the M6 yesterday because of a bad accident.
I don't know I could think of a good few miles of the Far North Line that would qualify - and no getting a boat in there either.![]()
I believe the local fire service now has a special road/rail vehicle for use in the Severn Tunnel in case of emergency.
Offer them free refreshments if facilities exist to do so.
Of course there are, from the pub!!
Due to the obvious difficulties in that scenario, the driver would (if possible), most likely continue with the train until they had exited the tunnel.The glaringly obvious one is the Severn Tunnel. It may be double-track, but if something catches fire down there (the worst possible situation) it clearly wouldn't be safe to approach and there is no convenient service tunnel to escape to. IIRC, there used to be a special rescue train kept at Severn Tunnel Junction with fire-fighting equipment and a means to get passengers out speedily. Not sure if that's still the case.
here it is : http://www.fire-engine-photos.com/picture/number31164.asp
supported bythis beast: http://www.fire-engine-photos.com/picture/number33294.asp
...that must be reachable in some form or another for track/ signal maintenance or re-fencing etc.
What about breaking down near Altnabreac?
Miles from anywhere, and three hours from Inverness for a rescue. Could get a bit chilly in the middle of winter...
Are there any trees up at Altnabreac...?
Joking aside, the chances are that the next train along would provide the assistance, even if it comes from the "wrong" direction, so the wait may not be as long as you suggest. But the chances are that the circumstances you describe are highly unlikely.
One of the advantages of DMUs are that each car is effectively self-contained. Even if one car is in the ditch, if the second car is the right way up there is a very good chance that it can still run to provide heat and light. If things really are as bad as you suggest, it's below freezing, there is no heat and light and no prospect of an assisting train, I would imagine that alternative arrangements would be made, even if it means coming via an RAF search and rescue helicopter.
O L Leigh

I think the point here is the time that it would take to get a rescue sorted.
The technical method may be the same as it would be anywhere else, but if (in this highly unlikely example) you had a train stranded here on a freezing winter's evening with deteriorating heating and lighting for the passengers and a tree stuck in the bogie... you'd be hard-pressed to keep people comfortable and get things fixed quickly.
In addition, what about waiting passengers? Again, this is seriously unlikely. However, Altnabreac is very high on my list of "Remote and/or generally desolate stations at which I would not enjoy being stranded in winter without camping equipment and thermal clothing".