Amtrak706

29 minutes ago, N6 Limited said:

Just got off a Far rockaway bound r179 train. When did they start running on the (A)? 

Four months ago

Just saw the latest 10-car set on a northbound test run at 181 St. It was running immediately behind the OG set (3010-3019) which was in revenue service.

“Insert other media” does not work at all so here is a link.

https://ibb.co/k1BfvBY

The R62s had an incredibly high MDBF, around 273,000 this past year, and the 62As maintained a very good 114,000. These are actually even higher than the R142 and R142A, respectively, and beat most other NTTs. They are by far the most reliable old tech trains and are in the top three for most reliable period, together with the R188 and R160. Why on earth is the MTA planning to replace them? When replacements were planned for the Redbird and then B-division SMEE fleets, MDBF was tanking and the cars were falling apart. I’m not saying they should wait until things are that bad again, but these cars solid stainless steel (not falling apart at all) and are so reliable that they may actually beat the R262s when they come in. It feels like a bad move.

1 hour ago, Lawrence St said:

But why didnt MTA just order new R142A's (or R188's) to replace the R62A's on the and kept the R62A as surplus cars or divide them evenly by each yard?

Because they would have been replacing them too early. They decided upon a certain amount of new cars for fleet expansion purposes, not to replace R62/As that were then between 26 and 28 years old and working well with a low MDBF.

Just saw 3015-3019 at 18 Av heading southbound on the Culver express track.

https://ibb.co/M9JPxFq
https://ibb.co/6JN03j0
https://ibb.co/vs0x2qz

Taken about 5 minutes ago

There are currently about 10 full size fire trucks at all the 181 St  entrances and delays going uptown. MTA.info says this is due to an “investigation”. Anyone know what happened?

DC motor cars use resistor banks as well as series and parallel relay configurations to manage acceleration. For example, if a T/O releases the brakes and immediately wraps the controller around to the "parallel" notch (full power) the train will not actually start in parallel. It will initially apply power in series configuration, and depending on the type of car this might be complemented with resistor banks to gradually increase current.

Around 10mph the car makes transition, which means the power control relay flips to parallel. This is that second "push" you may feel after a train takes off initially. Again, resistor banks may be used to manage the increase of current. Once the last resistor bank shuts off and the motors have full parallel current, the acceleration starts falling off from 2.5mph/s  at around 20mph and eventually stops at "balancing speed" between 35-45mph on level track.

Back in the day when field shunting was still enabled, several stages of field weakening or "shunting" (look this up online if you want a full electrical engineering description) would kick in to basically trade torque for speed by introducing a resistance to weaken the current in the field winding and ultimately the back EMF of the motor. This would allow a train to gradually reach its top design speed of 55mph, assuming level track.

The series notch on the controller will start a train out with the same resistor banks, but won't make transition to parallel. The first notch will start a train the same way except it leaves a few resistor banks on so the train never gets full series current. This notch is not used for more than a few seconds, as it could burn up the resistors.

All this is to explain that it makes no sense to advance gradually through the controller notches to manage acceleration. It is the same electrical process regardless of notch, you are just telling the controller where, or if, to pause the process.

For NTT trains with AC motors, none of this applies. Instead, the computer manages acceleration by modulating the AC current and frequency into the motors to stay at 2.5mph/s without wheelslip. The dropoff from this rate of acceleration does occur a bit later than on DC equipment, which is why R160s appear to "pull away" from R68As on Brighton. This took me a damn while to type so congrats if you are still reading.

Alright, here’s an interesting question: does anything in the museum fleet still have field shunting enabled? I would assume that the museum cars retired after the neutering in the late 90s (Redbirds, R32-R42) didn’t get it put back in, but I am wondering if the R10 and R16 or maybe that R33WF that got retired pre-GOH still have it enabled. If so, would that cause any issues when coupled to other museum cars without it?

I am currently in the first car of a C train, R160A 8624, as we creep uptown past the work zones on the CPW express track. There is an unbelievably loud hissing sound coming from the right side of the front truck. Could this be a leak in the airbag suspension or something? I have never heard this from a 160 before, it completely drowns out the loud HVAC and everything else. All the other passengers don’t seem to notice or care except for one woman at 59 St who was holding her ears in a kind of standing brace position. We have just opened the doors at 125 St as I post this

18 minutes ago, HenryB said:

I have a question.....does that mean  could remove those freaking timers after ATS installation?  

ATS centralizes dispatching. It is not a train control system. The IRT still has its fluff timers and it has had ATS for years.

4 hours ago, VIP said:

The  should just assume the   route after Hoyt Street to manhattan via 8 Avenue. Unless there aren’t any switches from the crosstown line...

Unfortunately there are not any switches from the crosstown line.

19 minutes ago, Bosco said:

3094-3097 are in at 207 St?  That would be weird considering we all know they're not going on the ...

They get delivered to 207. That set recently got delivered.

By the way, the pics above were taken by a friend of mine, not myself. He had to cut someone off to get 3100, lol.

3100 and 3101 on I-80E just east of Paterson NJ. 4:52 PM

Just heard from a friend that saw 3088 plus one more on I-80 around 9:30 this morning. If he took pics I will post them here.

R32s are Budd, not St. Louis. R42s are St. Louis.

So it seems that the R62As are finally dwindling on the . Once they are all gone, will that enable CBTC to finally start up or is there another issue that is precluding that?

You mean Church St? The 8 Ave line doesn't run under Chambers. In fact, Chambers doesn't have any lines under it. Theoretically it's just wide enough for a two-track line.

 

Church is five and a half lanes. The QBL runs under Broadway in Queens, which is even narrower. The Broadway line runs under Broadway in Manhattan, which manages to be even narrower than Broadway in Queens.

Yeah I meant the street the IND runs under there, not Chambers. And fair enough, it was a guess.

You're original post was written backwards kinda. The Chambers st platform is actually north of the WTC platform.

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Wow, brain fart. My bad.

 

The width of Chambers St in that area might also be a factor. It may not be wide enough to support two island platforms side by side.

I thought WTC (then Hudson Terminal) was arranged like that to provide a direct access to the H&M tubes

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Well the original Hudson Terminal platform was probably put as close as possible to the H&M. But the Chambers platform was designed to serve the Chambers St area, leaving the terminal station to serve Hudson Terminal (hence the names).

When the 8th Avenue and Fulton St lines were designed and built, the locals were intended to be only intra-borough routes, remaining in one borough, whereas the expresses would run between boroughs. The locals would mirror the IRT 9th Avenue and BMT Fulton St lines, with the locals intended to run between 168 Street and Hudson Terminal & Court St and ~Euclid Av. However, as funds dried up in the '30s during the Great Depression, the IND pretty much had no choice but to run the much-known route from 207 Street to Rockaway Av. It was either this or run three subpar routes which would not have been received well by the riding public. That's why we have the seemingly random build of Chambers St-World Trade Center and the, until 1976, useless IND station at Court St.

The IND actually built exactly what they had planned in this area. The Chambers St platform is slightly further south than the WTC terminal because the express tracks have to swing under and around the southbound local track after Canal St, and aren't quite done doing so where the terminal platform starts.

 

The IND operated with locals intra-borough and expresses inter-borough well after the Fulton St line was open. After people figured out it was kind of dumb, the locals were connected via the Cranberry branch.

 

The whole area between Canal and Chambers is partly convoluted because of the provision for IND Second System expansion to South 4th St.

How did the situation with World Trade Center/Chambers St being separate stations come to be? What did the IND think the benefits of that would be?

The original IND line that opened in 1932 was from 207 St to what is now the World Trade Center terminal, at the time called Hudson Terminal. The express tracks at Canal St were then extended separately via the Cranberry St tunnels to Brooklyn in 1933.

IIRC, no because SIRT didn't use acid baths to clean off graffiti. 

You know, I always wondered how no one predicted that drenching the cars like that would shorten their structural lives.

 

On a semi-related note, how come the R42s aren't as bad? They have non-stainless underframes and they sure got their share of acid baths.

Are the Staten Island R44s affected by the frame rot issue the NYCT R44s had? If so, how and why are they still in passenger service?

They've not broken the spec as far as I am aware. Starting acc should still be 2.5 mph/s. People are probably just visually misjudging the acceleration on these things from the videos.

 

You are correct; on the newer equipment, the traction computer limits the train to a pre-programmed acceleration profile, then controls the input to the motors to govern acceleration. It is possible, therefore, to change said acceleration profile if so desired, but I doubt it has been done in the videos that we've seen.

OK. Makes sense, thanks.