Has there ever been proposal to convert NHSL to subway Guage.

Dual gauge would be highly problematic.


Do you mean dual gauge between the Pennsylvania trolley gauge and standard? Dual gauge track between gauges differing by more than that does not seem to be highly problematic.

Myrtone wrote: ↑Sun Mar 20, 2022 7:04 pm Do you mean dual gauge between the Pennsylvania trolley gauge and standard? Dual gauge track between gauges differing by more than that does not seem to be highly problematic.

Yes. The whole point of forcing such a small difference on trolley lines was to preclude interoperation. Among other things PA's steam railroads were dead-set against allowing trolley operators to haul freight cars seamlessly.

Dual gauge with greater separation is of course highly practical. A notable transit example in the US was Los Angeles where standard and 42" gauges coexisted for decades. The major maintenance issue was that the shared side wore out faster, natch.

FWIW I found a few references to triple-gauge systems, again in Cincinnati as well as northeast PA and a couple of Australian states. https://upload.wikimedia.org/wikipedia/ ... 1120050226

JeffK wrote: ↑Mon Mar 21, 2022 10:00 am Yes. The whole point of forcing such a small difference on trolley lines was to preclude interoperation. Among other things PA's steam railroads were dead-set against allowing trolley operators to haul freight cars seamlessly.

Is it true that this factor is also why this gauge remains to this day on surviving large and interconnected networks with that gauge?

JeffK wrote: ↑Mon Mar 21, 2022 10:00 amDual gauge with greater separation is of course highly practical. A notable transit example in the US was Los Angeles where standard and 42" gauges coexisted for decades. The major maintenance issue was that the shared side wore out faster, natch.

There are other examples, some as part of a transition from one gauge to another.