Speed limits at Spuyten Duyvil

[CPSK]

Hi;
I am running the Dovetail TS2019 Hudson Line sim, and am curious to know how accurate the sim is to real life.
In the sim, the speed limit just south of CP12 goes down from 75 to 45, then returns to 75 for a short distance before lowering to 30 for the SD curve.
It makes no sense whatsoever to me that the speed limit would drop to 45, then return to 75 for such a short distance before a 30 mph curve.
Before I go any further on this, I would like to know what the actual speed limits are in this vicinity. I am aware that very often simulations are way off track when it comes to details.

Thanks for your help

CP

[DutchRailnut]

probably programmed wrong 45 would be speed if changing tracks in cp12, for straight moves it goes mp 11.5 to 18.5(yonkers curve) is 70
cp10 to mp 11.5 is 30 mph

[CPSK]

probably programmed wrong 45 would be speed if changing tracks in cp12, for straight moves it goes mp 11.5 to 18.5(yonkers curve) is 70
cp10 to mp 11.5 is 30 mph

Thanks. Yes, it does look like there are errors in the sim.
Another interesting thing I have learned by playing the sim is about signaling.
I was already aware that most (but not all) of the trackside signals were taken down many years ago, but what I didn't realize is that there is no true 'stop' condition built into the cab signaling system. From what I can tell, the only true stop signals are the home signals at the interlockings. I don't have a copy of the MNCR employee timetable, or any other rule book, so I could be very wrong here. This would appear to be a dangerous situation, which PTC makes a lot safer.
That said, can I assume that a restricting (R) signal requires the engineer to bring the train to a complete stop at some point before proceeding at restricted speed?
Were the same signal rules in effect on the Hudson line before PTC was installed?
All of this makes for a very interesting simulation. I am constantly finding myself receiving penalty braking applications because I am not attentive enough, or don't react quickly enough to the alerts. I am very new to driving in sims. I have spent most of my time building routes in Traniz.

I guess I should be going over to the Gaming & Simulations forum for my future posts on this subject.

CP

Edit: reading this thread from 2006: viewtopic.php?f=67&t=32448" onclick="window.open(this.href);return false;
I think I've got PTC mixed up with another automatic train control system. From what I have learned on that thread, an automatic control system has been in use on MNCR (and other passenger railroads, including the NYC subway system) for a very long time.

Edit 2: Am I confusing the term 'home' with 'CP'? My understanding is that all home signals are CP's, but I am not sure about the other way around. Or, are the terms used interchangeably?

[DutchRailnut]

correct cab/atc does not have a stop indication , the most restrictive is restricted cab (15 mph at MN)
so in all technical a train could have a 30 mph head on collision (15 & 15)
PTC does have a positive stop.
as for interlocking signal, it has stop/ proceed cab/ absolute block , (double red, flashing center green, or reds & green alternate flashing)

a home signal is an absolute signal at interlocking vs a permissive signal like in automatic intermediate signals (not used on MN)

a cp is interlocking controlled from another location (control point) on MN those are all controlled from operations center in NY.

[CPSK]

Thanks for the explanation.
I would think that the CTC 'machine' would make it impossible to route two trains in such a way that a head-on collision could occur.

[DutchRailnut]

correct, but trains have been known to pass a red signal.

[CPSK]

correct, but trains have been known to pass a red signal.

A Google search led me to the Anding MS 2005 wreck.
I read the pertinent parts of the NTSB report. Human error of course.
The report stated that a positive train control could have prevented the crash.
But here is a very unlikely scenario:

Assuming Metro North Railroad Hudson Line:
According to the sim I am running (TS2019 with Hudson Line add-on, with M7 cab car or P32AC-DM loco).

If you enter a new block and it has a reduced aspect (e.g. going from Normal to Limited) then the following happens and must be done by the engineer:  An alarm will go off in the cab.  The cab signalling will update to reflect the new signal speed and confirm what the new aspect is.  If the train is within the MAS (Maximum Allowed Speed) then the engineer must simply press the ACKNOWLEDGE button (Q key) within 8 seconds.  If the train is above MAS then the engineer must zero the throttle, move the brakes into 40% application or greater, and then press ACKNOWLEDGE within 8 seconds. (Note: It is not required to be within the speed limit during the 8 seconds, it is only required that the engineer has confirmed to the ATC system that they acknowledge the reduction in aspect and have taken appropriate action to comply with it.)  If the engineer moves the brake back out of suppression while still being above MAS then the alarm will sound again and the same procedure must be followed.  Failure to acknowledge correctly within 8 seconds means the brakes will go to full service application - however, the engineer can apply the same procedure as above and they will be able to regain control of the train without having to stop.  Once the train is under the new MAS the engineer can simply release the brakes and apply throttle as required.

Would it be possible for the engineer to repeatedly follow the above procedure, but never reduce the speed of his train to the MAS for the new signal, until the train reaches the next block at a speed greater than what is permitted, thus causing a crash? I realize that this scenario would require deliberate action on the part of the engineer; something that is so unlikely it could be considered impossible for all intents and purposes. A non-attentive or sleepy engineer would simply miss the cab signal and alerter, thus causing the train to go into emergency.
Although DTG just released the Hudson Line a few weeks ago, the coding most likely does not reflect the PTC (rather than ATC) system that is now in place on the line.
Would PTC be able to stop the train before it reaches the next block under these circumstances?

I guess I'm going to have to run the sim again and see if I can actually 'get away with' this.

From what I have read about PTC, it is a far more advanced system than what is sometimes referred to as 'ATC'. PTC involves radio as well as track signals, and GPS, thus can potentially determine the train's exact location and the appropriate action to take and when to take it. In addition, PTC can be implemented in the absence of any signalling system, using only track and radio signals, and GPS.

Does anyone remember the 'dead man's pedal'? I guess that was only to protect against an engineer who had fallen asleep, or had literally died on the job! It would also prevent a runaway train. I have read that it was common for the engineer to place his toolbox or other heavy object on top of the deadman's pedal, thus rendering it useless.

[DutchRailnut]

the alertor is even worse than the deadman, listening to it and reacting to it 400 times a day makes Engineer immune to it.
like a habitual sleeper and the snooze alarm , they will just hit it when asleep and not even know it.

[CPSK]

the alertor is even worse than the deadman, listening to it and reacting to it 400 times a day makes Engineer immune to it.
like a habitual sleeper and the snooze alarm , they will just hit it when asleep and not even know it.

I ran the sim again. It is obviously not coded for PTC, which is what I had assumed. It is coded only for ATC. My understanding of ATC is that it was designed a long time ago and is a rudimentary system that can prevent trains from running red signals, or entering blocks while exceeding the speed limit. However, at least in this simulation, ATC cannot prevent the train from speeding.
When an alert is sounded/displayed, all the engineer needs to do is follow the procedures to acknowledge it, but does not absolutely need to reduce the speed. I do not believe that (in the sim) there was any penalty braking applied, regardless of speed, so long as the engineer followed the procedure each time the alerter sounded.
I was even able to pass CP's while speeding, without the alerter even warning me that I was speeding. The only thing that did indicate excess speed was the flashing yellow bar on the HUD (which of course real trains do not have).
So, either this sim is not very realistic, or we should be very thankful that the old ATC is being replaced by the much more sophisticated PTC.

So far as having to acknowledge the alerter once every 60 seconds; is that still required with PTC? I would think not, since PTC should be capable of controlling the speed of the train, without interaction by the engineer. But then, I suppose it depends on what type of PTC has been implemented. From what I have read, there are many types used by the many RR's in the U.S., and that with each type there are levels of control that can be implemented.

Eventually, maybe 25 years from now, I suppose we won't need the engineer to actually drive the train. He will still need to be in the cab, but only for special cases or emergencies.

[DutchRailnut]

in real life ATC does force engineer to reduce speed, once you get a downgrade you have 6 seconds to apply the brake and and acknowledge the ATC downgrade .
releasing brake before speed is down to right level results in penalty application of brake.

[CPSK]

in real life ATC does force engineer to reduce speed, once you get a downgrade you have 6 seconds to apply the brake and and acknowledge the ATC downgrade .
releasing brake before speed is down to right level results in penalty application of brake.

OK. That makes sense. I guess when I ran the sim, I never released the brake; only returned it to the lap position.
I'll see how it works if I release it instead of lap.

[CPSK]

I just realized that I have been confusing speed changes. There are yellow markers on the sim's 'Driver Information' display (in the HUD, which of course, exists only in the sim) which indicate the upcoming speed limits. But these are not the same as what is indicated by the cab signals. It appears that, so long as there is a 'N' signal displayed in the cab, there will be no ATC alert when speed changes in the information display window. Only a downgrade (from N to L or L to M, etc) will trigger an alert.

[DutchRailnut]

you mentioned a lap function on brake, just for information there has not been a lap function on any passenger equipment since about 1993 when last FL-9's with 24Rl brake were retired.

[CPSK]

you mentioned a lap function on brake, just for information there has not been a lap function on any passenger equipment since about 1993 when last FL-9's with 24Rl brake were retired.

I guess I'm getting the Metro North trains confused with the CSX locos. I actually like the single control in the M7 cab over the separate brake and throttle controls in the P32AC, but I think it's mainly due to the method I am using to control the train - keyboard and mouse.

[DutchRailnut]

evenCSX has not had lap in 25 years .