The hosts are not trying to run off corridor traffic, they are trying to fend off grade xing accidents caused by Loss of Shunt with the passenger equipment. In fact the host railroads want the State money to upgrade their corridors and increase capacity.

Passenger equipment runs a different wheel profile (APTA 340), which was designed for high speeds, stability, and truck hunting prevention. The wheel profile accomplishes all of these things, but it also puts the wheel to rail contact onto a different area of the rail head. This profile also has a much smaller wheel to rail contact surface area.

The freight profiles have much more wheel to rail head contact surface area, and also allows trucks to wonder a bit, which causes flange to rail "hugging", which increases the freight equipments ability to properly shunt the signal systems.

Right now, the grade crossing manufacturers are working on the problem, which has become a hot topic with the host railroads in the past few years. In fact, there are a pair of Illinois Chargers that have different wheel profiles testing in the Midwest this summer. For California, the UP minimum axle count means 1 additional car or locomotive per train, which they do not have. For the PNW and Talgo equipment, this creates a problem, and you just cant add more Talgo cars, and nor do you want to add dead weight between the train set and the locomotive.
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> Amtrak/WSDOT are working on this, however, the
> Host Railroads nation wide are wanting to
> implement minimum axle counts to help with signal
> shunting. The CN/IC already is doing this in the
> Midwest, and both BNSF and UP are rattling their
> swords, with BNSF wanting a 24 axle minimum and UP
> a 30 axle minimum. If this happens, it further
> impacts Talgo operations in the PNW!

I can not comment on Metrolink and what they are thinking. As far as I know, most Metrolink trains operate on their own corridor,and BNSF and UP are guests.


> So for practical purposes the railroads
> (especially UP) don't want to run any passenger
> trains shorter than a Chief or Zephyr or
> Starlight? The corridor people don't have enough
> equipment (or the demand, for some trains) for (5
> car minimum on BNSF or) 6 or 7 car trains, if
> their locomotives could even handle that with any
> sort of acceleration. So for practical purposes
> those axle counts rule out corridor or commuter
> passenger service on UP lines. Is that the
> ulterior motive, or is it some actual failure in
> the PTC system? One presumes that in the past the
> 4-5 car (sometimes even 3 on commuter lines like
> Metrolink) trains that are common outside of rush
> hour would not have gotten lost in the
> dispatcher's office or failed to shunt signals ...
> and more than 6 cars (which is still too short for
> UP's minimum) is too long for a lot of station
> platforms now in use. Perhaps we need a lot more
> Cabbages - how many junk F40s are still around?