New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All • Hacker News Board

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#61

Post by rrdharan » Mon, Aug 07, 2017, 7:24 PM UTC

spyspy wrote: post #19

rrdharan wrote: post #12

Earlier quoted context omitted.

The problems with NYC subway signaling have been very extensively covered in previous reporting that you might find interesting: https://www.nytimes.com/2017/05/01/nyregion/new-york-subway-... http://www.nydailynews.com/new-york/nyc-subway-relies-decade... "Even something as basic as a cable is an antique. Workers popped open a junction box to show a 70-year-old cloth-covered cable, due for the scrap heap next year,…

> actually operates 24-7 Good one. They routinely shut down lines and stations for hours/days at a time. The L got shut down between Bedford & 8th Ave for the entirety of Memorial Day weekend. Even when lines are running perfectly, at night they only run once every 30-60 minutes. To riders the changes feel arbitrary and are impossible to predict. I've been stuck dozens of times in random places because I tried to use…

I'm not saying I haven't been caught inadvertently as well, but FWIW they actually do a pretty good job of posting all this information on their website.

And in fact Google Maps does a decent job of scraping it as well. You just need to remember that when Google Maps wants you to go to Jay St. Metrotech instead of High St it might not just be because it thinks it's 300m closer.

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#62

Post by aeorgnoieang » Mon, Aug 07, 2017, 7:25 PM UTC

marrone12 wrote: post #45

coldcode wrote: post #3

It would seem one could analyze the performance in this day of big data and find a more efficient plan for scheduling the trains and adjusting in real time. Maybe the system is too unpredictable to make this possible. Even so it would be fun to try to model the entire system and try.

The problem isn't in modeling the perfect train distribution, it is in that the system itself can't handle anything else. Many of the parts in the subway infrastructure are from the 40s and they just can't handle more trains.

> from the 40s

30s! And maybe even older!

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#63

Post by notmtaemployee » Mon, Aug 07, 2017, 7:27 PM UTC

The MTA's problems begin and end at a weak senior management unwilling to standup to Cuomo's frivolous micromanagement and a transit union unwilling to modernize.

Politicians should be pushing for serious procurement and labor work rule reforms, otherwise the systemic managerial and operational deficiencies will ensure that the deterioration of service we see now will repeat it self in 5 to 10 years, regardless of how much money or technology is poured into the MTA.

London and Toronto have been able to modernize much of their transit systems in last 5 years and its not because they have more money. Once you fix the top everything else will fall into place.

Look what Andy Byford has been able to do in 4 short years at the TTC. His 5-Year Plan to modernize the TTC focused on transforming corporate culture and updating internal processes, in addition to new equipment. The results of these changes have been overwhelmingly positive with the TTC recently being named best public transit agency in North America and The TR Class of TTC subway cars in May having a MDBF of over 924,000 miles.

If your interested in getting involved with transit activism in NYC I highly suggest you follow @2AvSagas on twitter.

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#64

Post by thrillgore » Mon, Aug 07, 2017, 7:30 PM UTC

pavement wrote: post #21

A lot of what affects the NYC subway is the principle of the "Sick System." http://issendai.livejournal.com/572510.html The system is too essential for a stop-the-world overhaul, but so far gone, that only a stop-the-world overhaul can part the clouds. Without a hard flush of antiquated mission critical infrastructure, millions of turbulent eddies and vortices will ensure that the system is always afflicted by parasi…

I have a better metaphor for this: It's too big to fail.

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#65

Post by aeorgnoieang » Mon, Aug 07, 2017, 7:30 PM UTC

Anyone know whether anyone's carefully considered simply adding new parallel systems, e.g. for signalling?

I can completely sympathize with the difficulty of upgrading 24/7 critical infrastructure, especially given that mistakes can kill or injure people. I'd try to just deploy separate parallel systems instead.

At a comically reduced scale, businesses migrating between ERPs (or similar line-of-business apps) often run both the old and new systems 'side-by-side' for some period of time. What I've never seen or heard them doing is trying to replace components or sub-systems of the old system with those of the new system. That kind of integration work would be awful and would probably drastically increase the odds that the migration would crash and burn.

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#66

Post by sliverstorm » Mon, Aug 07, 2017, 7:31 PM UTC

Joeri wrote: post #32

pavement wrote: post #21

A lot of what affects the NYC subway is the principle of the "Sick System." http://issendai.livejournal.com/572510.html The system is too essential for a stop-the-world overhaul, but so far gone, that only a stop-the-world overhaul can part the clouds. Without a hard flush of antiquated mission critical infrastructure, millions of turbulent eddies and vortices will ensure that the system is always afflicted by parasi…

Any sufficiently complex system will always run in degraded mode, because the individual mtbf rates for distinct elements will compound. Even a stop-the-world overhaul can't fix that, it will reduce the failure rate but it won't get rid of it. The trick to running such a system is to assume it is broken and still figure out ways of providing continuous service.

Case-study, large raid arrays. Last time I worked with one, it was exactly as you say, it was always degraded, and disks were constantly being replaced and arrays were constantly rebuilding.

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#67

Post by lasermike026 » Mon, Aug 07, 2017, 7:32 PM UTC

NYC MTA needs billions of dollars to fix the system. NY state must raise taxes on the rich and deploy it too the MTA. The federal must chip in too. The MTA will never make money and this is how it is.

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#68

Post by chiph » Mon, Aug 07, 2017, 7:37 PM UTC

pavement wrote: post #21

A lot of what affects the NYC subway is the principle of the "Sick System." http://issendai.livejournal.com/572510.html The system is too essential for a stop-the-world overhaul, but so far gone, that only a stop-the-world overhaul can part the clouds. Without a hard flush of antiquated mission critical infrastructure, millions of turbulent eddies and vortices will ensure that the system is always afflicted by parasi…

Not a New Yorker, but what I heard was that the tunnels only have two tracks, and both are needed for daily operations. So you can't replace one when it wears out because of the service interruption. If they had made the tunnels wide enough for three tracks, they'd have a spare for when they do repairs on one of them. And give them a place to do a rolling-upgrade of old middle-20th century signaling equipment.

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#69

Post by Nelkins » Mon, Aug 07, 2017, 7:41 PM UTC

The line about overcrowding being one of the major drivers behind delays doesn't hold much water. Ridership has essentially been flat or even declining in some areas[1] (peaked in early 2010s). Decreasing mean distance between failures in cars [2] (as well as mismanagement of crews & trains as mentioned in article) are among the main culprits.

[1] http://web.mta.info/nyct/facts/ridership/ridership_sub_annua...

[2] http://web.mta.info/mta/news/books/archive/160725_1030_NYCT.... <-- See page 29

Re: New York’s Subways Are Not Just Delayed, Some Trains Don’t Run at All

#70

Post by notmtaemployee » Mon, Aug 07, 2017, 7:42 PM UTC

aeorgnoieang wrote: post #65

Anyone know whether anyone's carefully considered simply adding new parallel systems, e.g. for signalling? I can completely sympathize with the difficulty of upgrading 24/7 critical infrastructure, especially given that mistakes can kill or injure people. I'd try to just deploy separate parallel systems instead. At a comically reduced scale, businesses migrating between ERPs (or similar line-of-business apps) often r…

When NYCT overlay's CBTC signalling on a line the block wayside system is upgraded at the same time and the two systems work in tandem. This allows non-CBTC equipped trains to operate over CBTC controlled territory and the wayside system functions as a backup should CBTC fail for any reason.

As you point the integration work for this is complex and is usually the primary driver of delays and cost increases.