Can't say I've ever been aware of any proposed use for freight siding connections Roger, though I'm no longer 'on the inside'.
But I do recall that 'someone' (a major infrastructure engineering contractor? - possibly one that began with a J) demonstrated a system called NICS (as you say, Non Intrusive Crossover System) to NR (West Coast Route Modernisation, and no doubt others) some 10 or so years ago.
But it was intended (then) to enable the very low speed crossing of engineering vehicles, on-track plant, etc. (not sure if designed to be suitable for large on-track machines or locomotives) between running lines (and possibly other very adjacent tracks I suppose) which were fully within an engineering possession, presumably where such a crossing facility would be very effective in allowing use of equipment in possessions on more than one track in turn (perhaps for a series of possessions in the same area on different dates) for fairly major works, but where no permanent crossover existed.
As to the form of NICS, I've an idea that it needed temporary (possibly pre-)installation (perhaps to only some sort of 'lightweight' standards) of those fixed rail elements of a crossover in the six-foot (and possibly both four-foots), necessary to part-form such a connection, but without fouling/intersecting/interrupting the normal 'straight' running rails and their flangeways.
The NICS crossover was I think then completed when required for use, once both tracks were under possession, by laying sections of heavy-duty platework on top of the 'straight' rails, to connect the temporary rails by equating to a normal crossover's switch rails and crossings, enabling the intended movement to cross by causing its weight to be borne by its wheel flanges while rolling, and raising it to pass above the permanent 'straight' rails.
Of course as part of relinquishing a possession and declaring the lines 'clear and safe to run on' for normal working, those in charge of the possession and its relevant worksite(s) would have had to ensure that the 'platework' had been completely removed : Any residual temporary rails which may still have been in place could be removed at any subsequent time when this could be safely done.
I seem to recall that at the time, 'the grapevine' word was that there were some doubts in NR as to the acceptability of the system, and I never heard of it again.
Last edited by StevieG
on Sun May 15, 2016 9:47 pm, edited 2 times in total.
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