Emergency cross-over (Metro North)

markpb

I've been reading the ABP reports on Metro North and came across this section:

Turn back facilities and emergency crossovers are required to allow LMVs to move between tracks to facilitate operational flexibility. Turn back facilities would be provided at Belinstown, St. Stephen’s Green, and between Fosterstown and Airport Stops. Emergency crossovers would be provided between Estuary and Seatown Stops, between the Airport south tunnel portal and Dardistown Stop, between Griffith Avenue Stop and the Ventilation Shaft, and between O’Connell Bridge and St. Stephen’s Green Stops.

So my question is, what's an emergency cross-over? What is the difference between a normal cross-over and an emergency one?

KC61

In the normal course of events crossovers would only be used where trams/trains regularly turn around.

For example, on the green line (as was prior to the extension opening) the only crossovers used normally are those at St Stephen's Green and Sandyford.

However, there are crossovers also at Beechwood and Ballally which are used only when there is a track closure for example. These are termed "emergency crossovers". They facilitate trams switching tracks and maintaining operations on some of the line,

markpb

Thanks for that So I guess it's more of an operational distinction than anything else?

KC61

markpb wrote: »

Thanks for that So I guess it's more of an operational distinction than anything else?

Correct.

trellheim

The few times I've seen the emergency LUAS ones used the driver has to get out with the big yellow pole to operate them.... so there must be something of a manual nature about them.

dowlingm

It's easier to have a (literally) manual switch than an expensive and hard to maintain auto switch. However, some transit systems (like the one I ride) all too often cheap out and install manual switches on more frequently used turnbacks (which can also cause speed limitations since if the manual is not reset properly there's a risk of derailment).

Colm R

Can the Luas 'cross over in an emergency manner :rolleyes:' on sections where it is mixed with normal road traffic like most of the red line?

KC61

Colm R wrote: »

Can the Luas 'cross over in an emergency manner :rolleyes:' on sections where it is mixed with normal road traffic like most of the red line?

On the red line there are "emergency" crossovers at Abbey, Smithfield, Blackhorse and Red Cow.

That's how they can keep operations going when part of the line is shut.

It's basically two sets of points joining the two tracks so that a tram can switch tracks.