[londons_explore]

> So instead of 30 minutes from Walthamstow to Brixton it'll be 8 minutes? How is that possible?

> There are 16 stations, or 14 stops excluding the terminii. If you stop for 30secs at each, that's 7 minutes in itself.

Or... you could stop at only 6 of the stops (express service). You could stop for 15 seconds door-open-time (as long as the crowd waiting for the train entirely fits on the train, thats very achievable - and crowd control can be managed by controlling platform ingress). Busses often achieve 3 seconds of door open time for comparison.

At a top speed of 60 mph, max acceleration of 0.2g, max jerk of 3 m/s^3 and travel distance of 2 miles per stop, the whole travel time becomes 13 minutes. Plus the 1.5 minutes for stops. =14.5 mins = 49 mph.

Lets schedule in one 30 second slowdown (ie. drunk guy holds door for mate for 30 seconds), and the average speed hits the 45 mph target.

I suspect the victoria line, being more modern in its track alignment, could easily be made to go 100 mph too...

[nsteel]

How do the express trains get around the slower stopping trains? Or are you going to entirely remove two thirds of the stops?! I don't think you'll have any risk of crowded platforms, it'll be far too useless a service to attract many passengers.

You cannot compare bus stopping times with tube stopping times. It's meaningless. But if you must, the average dwell time for a London bus is closer to 15 seconds. Which is actually quite remarkable when you consider you've got to pay as you get on. And there's often a buggy or two trying to negotiate the driver having parked too far from the curb. The peak and off-peak must be wildly different and make this single measurement pretty useless.

https://clondoner92.blogspot.com/2022/07/tfl-publishes-avera...

[walthamstow]

Ok, so your big plan for quadrupling the speed of the tube is for trains to breeze through most stations without stopping. It's like amputation as a weight-loss tactic.

[londons_explore]

Simulate it and see... The vast majority of journeys become quicker, even though many trains don't stop at many stations.

The optimal strategy is probably to have multiple express routes - ie. Train 1 stops at station A, C, E, and train 2 stops at B, D, and F. A better signalling system becomes necessary for that though - moving block signalling isn't sufficient - you need one that can take into account velocity-acceleration-jerk of both trains to get trains close enough while still ensuring passenger safety. That in turn requires Comms systems not just train presence information.