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| Why Do I Call It Bullshit? (1645364) | |
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| (1645365) | |
Re: Why Do I Call It Bullshit? |
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Posted by Stephen Bauman on Sun Nov 23 22:36:06 2025, in response to Why Do I Call It Bullshit?, posted by TRAIN DUDE on Sun Nov 23 20:21:46 2025. The news articles stated that NYCT had tested the wheels and tracks against spec and found them within spec. They never considered whether the specification was correct.In the 1990s the TA switched to ring damped wheels. Thanks for this insight. This may or may not be what's wrong with the spec. Further tests are required. Truck design for the R160's is a lot different from pre-1990 equipment. There may be lots of other suspects. They found that by reducing speeds, in some cases by just 5 MPH, the wheel wear issue was solved. This should be a quick and temporary solution to prevent the situation from getting worse. However, reducing speed should never be considered a permanent solution. The still need to find out why the new equipment does not perform as well as older equipment on these curves. They might have found a design fault to be the cause. The MTA might be hiding that finding to prevent more engineering competence questions from being raised. There was a similar situation with the Williamsburg Bridge crash. The emergency brake operated at half their spec. The MTA's solution was to slow down all trains to match their inferior brakes. |
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| (1645366) | |
Re: Why Do I Call It Bullshit? |
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Posted by Train Dude on Mon Nov 24 00:38:55 2025, in response to Re: Why Do I Call It Bullshit?, posted by Stephen Bauman on Sun Nov 23 22:36:06 2025. There was a similar situation with the Williamsburg Bridge crash. The emergency brake operated at half their spec. The MTA's solution was to slow down all trains to match their inferior brakes."This too was not the whole story. There was the installation of larger traction motors which increased the train HP by 15%. Speeds were increased but the timing of the signals was never adjusted for the additional speed. Hence during an emergency brake application on the williamsburg bridge, the signals did not provide a large enough block for an emergency brake application. However, reducing speed should never be considered a permanent solution. The still need to find out why the new equipment does not perform as well as older equipment on these curves. The (video) report I saw sort of intimated that this was the solution. That's why I called bullshit. I had my suspicions all along that the issue was more related to the trucks hunting in curves but this is not based on any data I've gotten. |
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Re: Why Do I Call It Bullshit? |
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Posted by trains61 on Mon Nov 24 01:01:29 2025, in response to Re: Why Do I Call It Bullshit?, posted by Train Dude on Mon Nov 24 00:38:55 2025. The other question I have, is why did this not effect M trains using the same equipment? To the unenlightened, could you please explain the "ring damped wheel" thing?Thanks in advance. The Lurkers' Guild |
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Re: Why Do I Call It Bullshit? |
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Posted by randyo on Mon Nov 24 02:34:15 2025, in response to Re: Why Do I Call It Bullshit?, posted by trains61 on Mon Nov 24 01:01:29 2025. While I don’t agree with the consultant’s assessment, IF it is to be relied upon, it could be inferred that the reason the the same equipment used on the M did not experience the same problem is because the M is running on the local tracks and at lower speeds than the cars used on the express services. |
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| (1645371) | |
Re: Why Do I Call It Bullshit? |
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Posted by Railman718 on Mon Nov 24 05:04:48 2025, in response to Why Do I Call It Bullshit?, posted by TRAIN DUDE on Sun Nov 23 20:21:46 2025. TD you said that the minute you was er informed about what they was going to do.. |
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Re: Why Do I Call It Bullshit? |
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Posted by Stephen Bauman on Mon Nov 24 07:08:55 2025, in response to Re: Why Do I Call It Bullshit?, posted by Train Dude on Mon Nov 24 00:38:55 2025. Hence during an emergency brake application on the williamsburg bridge, the signals did not provide a large enough block for an emergency brake application.I've discussed this before. The NTSB ran fully instrumented braking tests on the WB. The results were printed in the report. These results showed the speed when emergency brakes were applied and the distance it took to stop the train. It's possible to determine the braking rate from this data and the fact that the train was on a 2% uphill when emergency brakes were applied (also in the NTSB report). Based on this input, the emergency braking rate was something like 1.6 mph/sec, not the 3.0 mph/sec +/- 30% spec. Had the brakes been within spec, a collision would have been avoided by something like 50 ft. The explanation you just gave might be true but was not sufficient to cause the collision. Another design fault concerns the introduction of the R10's. They introduced higher speeds over pre-war equipment (BMT Multi's and experimentals excepted). Given the higher speeds, there was an equal design obligation to increase emergency braking rate so that the faster equipment was compatible with the signal system. That wasn't done. They actually made things worse by not applying the dynamic brakes during emergency application. It's important that the air brakes alone should be sufficient to stop the train but that's not an excuse not to apply the dynamic brakes during an emergency brake application. The NTSB did run a test when full service braking was applied, instead of emergency braking on the WB. The train came to a halt something like 150 ft short of a collision. |
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Re: Why Do I Call It Bullshit? |
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Posted by zac on Mon Nov 24 07:56:19 2025, in response to Why Do I Call It Bullshit?, posted by TRAIN DUDE on Sun Nov 23 20:21:46 2025. I have two questions. First, why wasn't any of this caught in testing? They tested the hell out of CBTC/ATO didn't they?And second, why was this so hush-hush? Somebody is hiding something. And if somebody is hiding something, then you can't rely on the conclusion. My conclusion has always been that they screwed up the testing and covered that up. See my first question. |
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Re: Why Do I Call It Bullshit? |
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Posted by Orange Blossom Special on Mon Nov 24 08:21:27 2025, in response to Why Do I Call It Bullshit?, posted by TRAIN DUDE on Sun Nov 23 20:21:46 2025. Yes, they got paid tons of money. Yes, they are friends or more likely a relative of someone higher up.Case closed, stop causing problems. The system moves too fast as it is. Trains need to move slower. |
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Re: Why Do I Call It Bullshit? |
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Posted by TRAIN DUDE on Mon Nov 24 08:29:57 2025, in response to Re: Why Do I Call It Bullshit?, posted by Stephen Bauman on Mon Nov 24 07:08:55 2025. I realize that you reported that before. I did not have R-42s to deal with on a day to day basis so I'm not aware of any changes to the braking. However across the fleet, i do not recall any changes to braking equipment. However shops did remove the final two steps of field shunting to slow the fleet because of the increased horse power. This, in my opinion was an error for the 75 foot cars as they were originally equipped with 115 HP traction motors and top speeds were never upgraded during overhaul as happened to the 60 ft cars. |
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Re: Why Do I Call It Bullshit? |
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Posted by TRAIN DUDE on Mon Nov 24 08:37:39 2025, in response to Re: Why Do I Call It Bullshit?, posted by zac on Mon Nov 24 07:56:19 2025. Every fleet of cars is required to have annual brake testing. Ra dom trains are tested for stopping distance in full service braking and in emergency braking in light load and in heavy load where weights are loaded into cars to simulate a heavy load. I never heard of any fleet of cars where the full service or the emergency braking did not meet the required stopping distances. This fact is at odds with the NTSB report as related here. |
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| (1645377) | |
Ring Damped Wheels Re: Why Do I Call It Bullshit? |
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Posted by TRAIN DUDE on Mon Nov 24 08:47:33 2025, in response to Re: Why Do I Call It Bullshit?, posted by trains61 on Mon Nov 24 01:01:29 2025. I'll try. In short, a ring damped wheel is a wheel where a groove is cut into the inner circumference of the wheel tread. A spring steel rod is pressed into that groove of absorb excess energy emitted through the wheels. This energy is given off as sound. The ring damping mearly quiets the wheel, mostly on curves. Google does touch on this topic lightly. |
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Re: Ring Damped Wheels Re: Why Do I Call It Bullshit? |
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Posted by steamdriven on Mon Nov 24 14:25:39 2025, in response to Ring Damped Wheels Re: Why Do I Call It Bullshit?, posted by TRAIN DUDE on Mon Nov 24 08:47:33 2025. " However, reducing speed should never be considered a permanent solution."Of course this is the permanent solution. Wasting your time and creating a sense of frustration is a prime directive at NYCTA. If said mission requires wearing the equipment by brake on/brake off cycles between stops, so much the better. *Yes I know there are some at Transit, possibly even in management, who try to make it work. When riding the system it's clear those well-intentioned souls are outnumbered and outgunned. |
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Re: Why Do I Call It Bullshit? |
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Posted by steamdriven on Mon Nov 24 14:43:59 2025, in response to Re: Why Do I Call It Bullshit?, posted by Stephen Bauman on Mon Nov 24 07:08:55 2025. " 1.6 mph/sec" ... emergency brakingThat's just sad. They could have found that with less than an hour of testing per train - much less. Even 3.0 is sad, PCCs did better than twice that. At least make it 4.0, a touch greater than full normal. Having been on them when they used the track brake, I can say the PCC and LRV track braking was not too much if you pay attention when the buzzer sounds (there was a buzzer that sounded when extra super stop this thing was activated). If you were standing with knees locked and earbuds on Smooth Jazz, you might topple... which is a lesson one needs to learn at some point anyways. The Boeing LRVs brakes were noticeably better than PCCs. The one time I felt them it was more like being in a car as if slowing for a red light when you thought you'd make it through the yellow. Well less than the full grip of rubber on pavement, but impressive for steel on steel. I wonder if the track brakes had some sort of friction material. |
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| (1645391) | |
Re: Why Do I Call It Bullshit? |
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Posted by Stephen Bauman on Mon Nov 24 19:54:03 2025, in response to Re: Why Do I Call It Bullshit?, posted by steamdriven on Mon Nov 24 14:43:59 2025. Even 3.0 is sad, PCCs did better than twice that. At least make it 4.0, a touch greater than full normal.The PCC's and the Bluebirds used track brakes. There's a serious limitation on braking rate, if braking is applied through the wheels (either with tread or disk brakes). The wheels must maintain adhesion with the rails because the coefficient of rolling friction is greater than the coefficient of sliding friction. I can say the PCC and LRV track braking was not too much if you pay attention I wasn't paying too much attention, when I experienced my single experience of a PCC track brake application. I was riding the Riverside Line on Boston's MTA, back in the early 60's. It went through a golf course. I was standing near the rear doors. A golfer was attempting to make a shot, in the middle of the tracks. The braking threw me against the windshield - half a car length from where I was standing. |
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Re: Why Do I Call It Bullshit? |
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Posted by randyo on Tue Nov 25 03:46:21 2025, in response to Re: Why Do I Call It Bullshit?, posted by Stephen Bauman on Mon Nov 24 19:54:03 2025. I had a similar experience riding Commonwealth Av in Boston. I observed that some dumb motorist attempted to make a u turn about a block away from the trolley and heard a buzzer go off. I yelled to my wife to hold on because as a former M/M i knew what was about to happen. Within a half a block the trolley stopped although I can't say the same for the passengers. |
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Re: Why Do I Call It Bullshit? |
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Posted by randyo on Tue Nov 25 03:50:00 2025, in response to Re: Why Do I Call It Bullshit?, posted by Orange Blossom Special on Mon Nov 24 08:21:27 2025. Based on what I have seen on other transit systems in the US, NYCTS trains move entirely too slow. |
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Re: Ring Damped Wheels Re: Why Do I Call It Bullshit? |
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Posted by Wallyhorse on Tue Dec 16 14:22:34 2025, in response to Re: Ring Damped Wheels Re: Why Do I Call It Bullshit?, posted by steamdriven on Mon Nov 24 14:25:39 2025. And as much as some don't like it this likely makes the most sense. |
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