i’ve always wondered this
lightrail, streetcars, trams. Why must they be built to be incompatible with heavy rail? why can’t heavy rail be built with a bunch of level crossings, street level stations, slow speeds, and function exactly the same as light rail?
if compatible, the rail could act heavy at designated tracks and light at others, removing what would otherwise be an interchange. it would also allow the light rail to have a higher top speed at express areas.
what am i missing?
Light rail is typically used in situations where it is fitting the trains into smaller spaces, often sharing space with other modes of transport. Building it to a heavier grade would cost more and offer no benefit. Even if you spend the money to build a light rail line to support a longer, heavier, faster train, you could not run that train anyway, because the spaces is shared, the turns may be too tight, the bridges may be too low, there may be no space for platforms. It is more cost and space effective to have separate lines.
Note, many light rail networks use standard gauges, so they can use standard maintenance equipment.
space issue, makes sense