‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
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Re: ‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
#2> It’s not as simple as just changing the signal. In order to change it out and modernize, you need to update the entire system.
Does anyone have any idea why this is? What prevents new signals from being backwards compatible with the old system?
And if this were true, wouldn't all of the signals need to be the same hundred year old type? How would line extensions ever be able to be done in that case? Is the system segmented in some sense? If it is segmented, what prevents further segmentation to allow incremental updates of the signals?
Re: ‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
#3> It’s not as simple as just changing the signal. In order to change it out and modernize, you need to update the entire system. Does anyone have any idea why this is? What prevents new signals from being backwards compatible with the old system? And if this were true, wouldn't all of the signals need to be the same hundred year old type? How would line extensions ever be able to be done in that case? Is the system s…
I agree that that is a puzzling statement.
Perhaps the intent was to say something like "you can't reap marginal benefits from the replacement of a single signal since the whole system must be modernized to allow the advanced signalling afforded by new technology," or something.
Re: ‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
#4> It’s not as simple as just changing the signal. In order to change it out and modernize, you need to update the entire system. Does anyone have any idea why this is? What prevents new signals from being backwards compatible with the old system? And if this were true, wouldn't all of the signals need to be the same hundred year old type? How would line extensions ever be able to be done in that case? Is the system s…
> Does anyone have any idea why this is? What prevents new signals from being backwards compatible with the old system?
Presumably you can't use anything currently manufactured.
So, you'd have to commission a unique, backward compatible design. And test it. And qualify it.
And no company is going to do that without you basically paying them the same up-front amount as if you just contracted to replace all the signals.
Re: ‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
#5The Atlantic did a great longform piece last year all about NYC's (also past-useful-life) signaling infrastructure by asking a simple question: why is it so hard to build a train arrival countdown clock?
They go into a lot of detail on how the past-useful-live infrastructure works, modern replacement technologies, and even a race between infrastructure-giant Siemans and a bunch of hackers kludging together a countdown clock:
http://www.theatlantic.com/technology/archive/2015/11/why-do...
A more interesting read than this blog post.
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On a different note, these "they don't make these anymore" problems make me wonder if maybe we should be pushing government to look for open-source hardware for these types of infrastructure work.
When you have equipment lifetimes of (officially) 35 years (realistically up to 100 years), can you really rely on the same Sieman's division to still be in business supporting it? In this Boston story, I wonder how much of their repair workshop is reverse-engineering some hardware whos blueprints long ago decayed in some rusting factory.
Given the right open-source hardware, could you make "they don't make these anymore" obsolete because the technology has become accessible enough that you could build it yourself? (And in the process employing "New Economy" type high-tech jobs). More importantly, should a public entity push for making it's infrastructure publicly accessible? (Pragmatically, could you find someone to build it under those terms?)
Re: ‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
#6live in MA and take the T (what we call the subway/bus service here). Public transit is a major problem in this city and surrounding areas. It what make this city OK and expensive vs being great and affordable.
While the transit system here needs upgrading badly, this piece is very political. The quoting of Charles Chieppo is a give away.
"For many systems, Chieppo said, the focus is on improving stations or opening new ones rather than fixing the core infrastructure." The T is working on the first expansion of the subway rail system since the 1980s. Its going into the neighboring city of Somerville and "surprise" its over budget. They might kill the expansion with the focus on "fixing the existing" as kind of justification, instead of doing both at once? They're also reducing late night service for the extra couple hours they tacked on to friday and saturday, while proposing a fair hike. Things cost money, but people don't like to pay more to get less.
(I'm actually usually on one of the MASCO "private" buses that supplement the T for its failure to provide adequate routing to the Longwood Medical area.)
Re: ‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
#7> It’s not as simple as just changing the signal. In order to change it out and modernize, you need to update the entire system. Does anyone have any idea why this is? What prevents new signals from being backwards compatible with the old system? And if this were true, wouldn't all of the signals need to be the same hundred year old type? How would line extensions ever be able to be done in that case? Is the system s…
Because the old signals systems are analog or electromechanical, all modern signals systems are computerized. You'd essentially have to build something custom from scratch to do so, which would be way more expensive than simply replacing everything. Since both options sound unappetizing, they end up doing patch repairs like this to keep the system going, but that can only last so long before it just breaks down.
Re: ‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
#8> It’s not as simple as just changing the signal. In order to change it out and modernize, you need to update the entire system. Does anyone have any idea why this is? What prevents new signals from being backwards compatible with the old system? And if this were true, wouldn't all of the signals need to be the same hundred year old type? How would line extensions ever be able to be done in that case? Is the system s…
I agree that that is a puzzling statement. Perhaps the intent was to say something like "you can't reap marginal benefits from the replacement of a single signal since the whole system must be modernized to allow the advanced signalling afforded by new technology," or something.
Its actually worse, in that replacing 1% of switches means the switch repair shop and field techs now have to learn 100% more and stock 100% varieties of spare parts etc. Eventually a breakeven point is found where the reduction in labor on the old switches exceeds the cost of being dual capable.
Its possible to imagine numbers where the cost of being dual capable is so high, the cheapest solution is some kind of forklift upgrade of the whole system. Which is kinda what they're doing.
A good hardware analogy is you have a company thats a windoze PC shop. Maybe even all the hardware comes from the same Dell contract, same OS image on every box, its pretty cheap. Surely OSX would improve any end user experience, but imagine the cost of instantly doubling the helpdesk workload to now handle two kinds of hardware and two OS images and two licensing agreements and generally two of everything.
Or a good software analogy is given a somewhat reliable mysql cluster, dropping postgresql on it and trying to use both at the same time is likely to result in some heartache.
Re: ‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
#9The Atlantic did a great longform piece last year all about NYC's (also past-useful-life) signaling infrastructure by asking a simple question: why is it so hard to build a train arrival countdown clock? They go into a lot of detail on how the past-useful-live infrastructure works, modern replacement technologies, and even a race between infrastructure-giant Siemans and a bunch of hackers kludging together a countdow…
That particular problem is easily solved by providing all needed documentation as part of the development contract. I'm a big fan of OSS & OSH, but it doesn't add value in this case.
I'm pretty sure the problem isn't knowing how the devices work, it's the limitations of the 100 year-old technology in the face of modern expectations.
Re: ‘They Don’t Make These Anymore’: Maintaining the MBTA’s 100-Year-Old Signals
#10> It’s not as simple as just changing the signal. In order to change it out and modernize, you need to update the entire system. Does anyone have any idea why this is? What prevents new signals from being backwards compatible with the old system? And if this were true, wouldn't all of the signals need to be the same hundred year old type? How would line extensions ever be able to be done in that case? Is the system s…
Because the old signals systems are analog or electromechanical, all modern signals systems are computerized. You'd essentially have to build something custom from scratch to do so, which would be way more expensive than simply replacing everything. Since both options sound unappetizing, they end up doing patch repairs like this to keep the system going, but that can only last so long before it just breaks down.
^ that
The Atlantic article linked above covers this in more detail, and is an excellent read all-around.