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A comment on America’s Havana: Thousands Say “Ciao” to San Francisco.

Re:America’s Havana: Thousands Say “Ciao” to San Francisco by Lammy on Tuesday May 12, 2020 @07:33PM (#23161415)
> Even the sights and sounds of the city suggest a certain derangement. When the Bay Area Rapid Transit (BART) system was first built in the 1970s, its designers failed to understand the acoustics between wheel, track, and tunnel. Since the nineteenth century, competent railroad engineers have known that a tapered, flanged wheel will handle turns better and generate less noise. For some reason, BART designers ignored this design in favor of a cylindrical wheel with a straight edge.

The "some reason" was to withstand the crosswinds on the Golden Gate Bridge. We only use the top of the bridge's two possible decks, and the bottom deck was slated to carry the BART Marin line: https://i.imgur.com/hVT6fya.jpg

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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by mc32 on Tuesday May 12, 2020 @07:38PM (#23161465)
Isn’t BaRT going ahead and tapering the wheels time reduce the noise? I think I heard there was one measure they were taking.
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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by necubi on Tuesday May 12, 2020 @07:41PM (#23161494)
They already did, a few years ago. It's much, much better than it used to be—you can now have a conversation in the transbay tube. And the new cars ("Fleet of the Future") are actually quite pleasant, although they've been rolling out very slowly.
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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by mc32 on Tuesday May 12, 2020 @07:45PM (#23161536)
The worst if it wasn’t the tube so much as the MacArthur and the Berkeley interchanges as well as the civic center- 16th street dogleg.
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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by dweekly on Tuesday May 12, 2020 @07:37PM (#23161457)
Seems they are working on changing the wheel shape.

https://sf.streetsblog.org/2018/06/08/bart-makes-headway-aga...

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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by refurb on Tuesday May 12, 2020 @07:34PM (#23161428)
OK, but freight trains use the normal wheels everywhere else in America, including very windy places.
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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by ashtonkem on Tuesday May 12, 2020 @07:48PM (#23161562)
Freight trains are much heavier on the same gauge. The weight limit for a BART train loaded is 55 tons. Compare that to a freight car which weighs 30 tons empty, but can carry up to 100 tons worth of stuff inside it.
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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by refurb on Tuesday May 12, 2020 @07:56PM (#23161635)
OK, but I assume those trains are sometimes moved around empty?
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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by ashtonkem on Tuesday May 12, 2020 @08:17PM (#23161838)
Ideally no. But a lot of them are also flat beds and cattle cars that’ll let air through them when totally empty.

I’m assuming that wind is taken in as a factor when deciding what stock to send where though.

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Re:America’s Havana: Thousands Say “Ciao” to San Francisco by refurb on Tuesday May 12, 2020 @08:36PM (#23161999)
You do hear of derailments due to wind sometimes for empty freight cars.

https://en.wikipedia.org/wiki/List_of_wind-related_railway_a...

Interesting stuff!

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