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by kderbe 658 days ago
Anyone interested in Caltrain operation should check out the Caltrain HSR blog, https://caltrain-hsr.blogspot.com/. It's not just about high-speed rail. For example, last week the blog pointed out that the new trains take an extra 8-10 seconds after stopping at a station to begin opening the doors. Which chews up 12% of the trip time savings achieved by the move from diesel to electrified trains!
4 comments

> For example, last week the blog pointed out that the new trains take an extra 8-10 seconds after stopping at a station to begin opening the doors

Anecdotally, this is also true of the San Francisco Municipal subway. The subway cars take a long time to open and close doors because there is a mechanical bridge that closes the gap between the train and the platform. This is also a pretty big time sink for the subway system

In contrast, in the metro in Paris, the doors open a few seconds before the train stops, so that the doors are fully open by the time the train is stopped - and passengers in a hurry can jump out while the train is still moving.
Not sure if they still have the wooden cars on the A (blue) Subte line in Buenos Aires. I lived in Caballito for a little while in 2007 and got a huge kick out of opening the doors early, hopping off the train and sliding on the platform with my crappy slippery shoes.
In Berlin (and probably other German subway systems, can't recall) you can trigger the open doors handle/button a few moments before the train completely stops, similar concept to Paris.
I experienced a few German S-Bahn systems. Berlin's seems to be the only one that doesn't use trains similar to the regional ones, which have the delay.
Is this a new feature? None of the metro trains in Paris did that a few weeks ago.
It's an old feature. You have to open the door manually, and the new trains (especially on automated lines) don't allow this.
> because there is a mechanical bridge that closes the gap

No. It's because the whole thing is crazy slow. Fear of lawsuits? I don't know. The door warnings on Caltrain, Bart, Muni are often comically offset compared to the door motions. That is, too late to be useful as legal warnings.

That delay wasn't an issue with Muni's previous trains which also had moving stairs.
> As seen in the timeline graphic, allowing the step to deploy and retract while the train is in motion would remove this wasted dwell time.

It's interesting... I wonder if extending the step while the train is in motion has the potential to knock people down who's currently on the platform and standing too close to the train.

> since the step itself does not extend over the platform (it reaches only 63.5 inches from vehicle center line when fully extended) there can be no hazard to passengers

I dunno about that. What if they had an umbrella or grocery bag or such dangling over the platform edge?

----

Maybe the more relevant question is how was it done before? Did the old train also have slowly-extending steps? How is it handled in other countries with functional train networks?

> Maybe the more relevant question is how was it done before? Did the old train also have slowly-extending steps?

Fixed, non-moving stairs. IIRC, the bombardier model was 2 steps (one step up to a metal stair, one more step into car) and fairly easy, and the older gallery models were a bunch of stairs and a pretty steep climb.

> How is it handled in other countries with functional train networks?

Level boarding, no? IIRC NYC's commuter rail is level boarding within The City (but not further out like CT) and, e.g., the more subway-y line of the T in Boston are level boarding, but those are subway. (I don't recall the MBTA's commuter rail, but I suspect it isn't, or isn't everywhere.)

They are ingenious, and can make even level boarding slow. See Muni.
The delay observed happens after the train has stopped. The delay is due to laggy software and can be eliminated without extending anything from the train while it's moving.

The old trains have no moving steps.

The video is showing part of that delay, but the blog entry is explicitly suggesting that the step start extending while the train is still in moving (at < 5 mph):

> This can be fixed in software. As seen in the timeline graphic, allowing the step to deploy and retract while the train is in motion would remove this wasted dwell time.

> I dunno about that. What if they had an umbrella or grocery bag or such dangling over the platform edge?

If it's over the edge the train itself will take their arm with it.

Per the video, the rest of the train is a relatively smooth, consistently flat surface: https://x.com/clem_tillier/status/1822833211019546624

The step does stick out a little more.

That's interesting and I hope it can be improved -- but with all due respect to Clem Tiller's expertise, I disagree about it affecting even 12% of the most important figure.

My understanding is that the primary overall improvement is about the additional service hours that can be provided by the new trains.

Yes, it's nice to shorten the time for an individual traveling SF <-> SJ... but the benefits compound even more because now Caltrain can offer more trips per day using the same number of train consists.

> the new trains take an extra 8-10 seconds after stopping at a station to begin opening the doors

Why?

For the stairs to extend without anyone near them being caught unawares