Very true, though the powerful lighting fitted today seems to do a very good job of both. I recall a Class 150 cab ride in the dark with the orignal lighting clusters and visibility was practically nil!It's worth bearing in mind that train headlights are less to illuminate the line ahead and more to act as a marker so that people can see the train coming.
As built they had the left 'night' light only. Most Northern 142s now have a 'day' light now.Just add another small thing. Class 142s since built (and most still do) only have one headlight. I think its the day setting? Northern have been modifying the fleet recently for both day and night headlights.
That's a bit of a minefield in my experience. I think there must be some sort of 'memorandum of understanding' for LU vehicles on NR metals, and as discussed before, the 'yellow panel' isn't used by them either. I know LU don't normally allow track workers or patrolling during operating hours, so their own rules (ie for pure LU infrastructure) have less visibility requirements, as there should never be anyone on or about their lines.In that document, i couldn't instantly see an exemption for LU vehicles.
The answer like many of this kind is to be found back in the 1970s.I'm sure the answer is simple, but why do trains have one headlight on one side and just a marker light on the other? How come it isn't a standard 2 like cars?