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How we slowed the subway down

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Re: How we slowed the subway down

#2
The obvious solution seems to be to technically enforce the speed limits without relying on average-speed-through-section, which seems to have been done way too late.

Likewise, the yellow signals could trigger enforcement of a braking curve to ensure the train will have a sufficiently low speed at the next red signal. (This is how one of the German systems works - PZB, not a modern one either, I think the braking-curve-enforcement was introduced in the 1950s.)

Especially if the "too much acceleration" problem only applies to new trains, that also conveniently addresses the upgrading issue - old trains accelerate slow enough to be safe under the old rules, new trains can have e.g. a speed limiter.

It's also just one subway system, not an entire national railway network, which should make modernization a lot easier. But I guess given that apparently actually using regenerative braking was a new thing in 2018 (https://www.progressiverailroading.com/sustainability/news/M...) despite the heat issues in the stations, I guess that's expecting too much.

Re: How we slowed the subway down

#3
After an operator-error derailment on the commuter rail line I frequently ride, the response of the NTSB was to require the railroad de-prioritize on-time performance and increase schedule times. As a frequent rider on the route I would much rather have my 15 minutes per day back and risk a once-per-century fatal accident. But the risk-averse bureaucracy we've built doesn't make such calculations with a balance like that: they prioritize safety above all else never mind the detriments.

Re: How we slowed the subway down

#4
post #3

After an operator-error derailment on the commuter rail line I frequently ride, the response of the NTSB was to require the railroad de-prioritize on-time performance and increase schedule times. As a frequent rider on the route I would much rather have my 15 minutes per day back and risk a once-per-century fatal accident. But the risk-averse bureaucracy we've built doesn't make such calculations with a balance like…

It’s not a bureaucracy thing IMO

People are severely spooked when they hear people are injured

If you have customers and you want to continue having customers, you really have to manage your PR. Injuries look really bad

Re: How we slowed the subway down

#5
post #3

After an operator-error derailment on the commuter rail line I frequently ride, the response of the NTSB was to require the railroad de-prioritize on-time performance and increase schedule times. As a frequent rider on the route I would much rather have my 15 minutes per day back and risk a once-per-century fatal accident. But the risk-averse bureaucracy we've built doesn't make such calculations with a balance like…

"Sure you save some lives but how many will be late!" I do not like this math. For example the accident may not be once per century. And it is good for the bureaucracy to be risk adverse if it comes to my life.

The answer is that they should improve the technology so that the system is safe and faster.

Re: How we slowed the subway down

#6
post #5
post #3

After an operator-error derailment on the commuter rail line I frequently ride, the response of the NTSB was to require the railroad de-prioritize on-time performance and increase schedule times. As a frequent rider on the route I would much rather have my 15 minutes per day back and risk a once-per-century fatal accident. But the risk-averse bureaucracy we've built doesn't make such calculations with a balance like…

"Sure you save some lives but how many will be late!" I do not like this math. For example the accident may not be once per century. And it is good for the bureaucracy to be risk adverse if it comes to my life. The answer is that they should improve the technology so that the system is safe and faster.

Many lifetimes of time are being wasted every day to save < 10 lives every century.

Re: How we slowed the subway down

#7
post #5
post #3

After an operator-error derailment on the commuter rail line I frequently ride, the response of the NTSB was to require the railroad de-prioritize on-time performance and increase schedule times. As a frequent rider on the route I would much rather have my 15 minutes per day back and risk a once-per-century fatal accident. But the risk-averse bureaucracy we've built doesn't make such calculations with a balance like…

"Sure you save some lives but how many will be late!" I do not like this math. For example the accident may not be once per century. And it is good for the bureaucracy to be risk adverse if it comes to my life. The answer is that they should improve the technology so that the system is safe and faster.

If OP's subway carried 80k people per day (and I guess this could be conservative), and they are all delayed 15 minutes, the overall wasted time equals 1 lifetime per month.

I'm all for improving the technology, but in the meantime the math should absolutely be done, at least to ensure the temporary fix isn't worse than the problem.

Re: How we slowed the subway down

#8
post #6
post #5

Earlier quoted context omitted.

"Sure you save some lives but how many will be late!" I do not like this math. For example the accident may not be once per century. And it is good for the bureaucracy to be risk adverse if it comes to my life. The answer is that they should improve the technology so that the system is safe and faster.

Many lifetimes of time are being wasted every day to save < 10 lives every century.

Lifetimes aren't composed of tiny time slices of many people.

Re: How we slowed the subway down

#9
post #6
post #5

Earlier quoted context omitted.

"Sure you save some lives but how many will be late!" I do not like this math. For example the accident may not be once per century. And it is good for the bureaucracy to be risk adverse if it comes to my life. The answer is that they should improve the technology so that the system is safe and faster.

Many lifetimes of time are being wasted every day to save < 10 lives every century.

Life can't be reduced to (productive) time like this. At least I find this take very sad.

Re: How we slowed the subway down

#10
post #5
post #3

After an operator-error derailment on the commuter rail line I frequently ride, the response of the NTSB was to require the railroad de-prioritize on-time performance and increase schedule times. As a frequent rider on the route I would much rather have my 15 minutes per day back and risk a once-per-century fatal accident. But the risk-averse bureaucracy we've built doesn't make such calculations with a balance like…

"Sure you save some lives but how many will be late!" I do not like this math. For example the accident may not be once per century. And it is good for the bureaucracy to be risk adverse if it comes to my life. The answer is that they should improve the technology so that the system is safe and faster.

Practically what happens is many people switch to driving and waste more lives
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