Slashdot Mirror
Rethinking Rail Travel: Boarding a Moving Train
PolygamousRanchKid tips this article about an idea for revolutionizing the rail system in the long-term:
"The idea is to have a city-wide network of trams that travel in a loop and connect with a high-speed rail service. But instead of passengers having to get off the tram at a rail station and wait for the next HSR service to arrive, the moving tram would 'dock' with a moving train, allowing passengers to cross between tram and train without either vehicle ever stopping. 'The trams speed up and the high-speed train slows down and they join, so they dock at high speed,' explains Priestman. 'They stay docked for the same amount of time that it would stop at a station,' he adds. While Priestman admits that it will be some time before his vision could be implemented, he says the time has come to rethink how we travel. 'This idea is a far-future thought but wouldn't it be brilliant to just re-evaluate and just re-think the whole process?' he says."
1. You're going to need a lot of extra right-of-way for your low-2-high-speed train to loop back - unless you then bring it to a complete stop, and backtrack - covering 4x the distance (2x each way), and needed to accelerate twice instead of once, so 2x the energy, and the people are delayed by 4x to get off at the destination of the slow-speed train, more than eliminating any time saved in getting on.
2. If you make the stops too close together, you might as well just connect them directly with the train that actually stops.
3. If you make them far apart enough for this to be practical, then each slow-speed train has to carry a lot more people - making it in effect another high-speed train that might as well just stop, because it's a lot cheaper to buy 1 and maintain 1 high-speed train than it is 5 or 6 to service the same route.
4. The high-speed train has to stop for maintenance and cleaning anyway (or is it just going to keep getting dirtier and dirtier as time goes on until it becomes a moving trash heap)?