There is a picture of the PTC box in 4014 on the website under a post of what changes the 4014 has for the 2021 trip on the Trains web site.
https://www.trains.com/trn/railroads/locomotives/union-pacific-big-boy-differences-from-2019-tour/
Big Bill "The UP fleet will operate, of course..." Nowhere have I seen anything, anywhere (maybe I'm looking in the wrong places?), about PTC being installed on the Big Boy. Or the 4-8-4. Or the Challenger. Did I miss it? I don't see how a diesel in the consist will stop any of these machines. Maybe I'm all wrong, it's happened before.
"The UP fleet will operate, of course..."
Nowhere have I seen anything, anywhere (maybe I'm looking in the wrong places?), about PTC being installed on the Big Boy. Or the 4-8-4. Or the Challenger.
Did I miss it?
I don't see how a diesel in the consist will stop any of these machines.
Maybe I'm all wrong, it's happened before.
UP 4015 has now operable PTC using the some of the onboard functions via the trailing diesel engine. UP 844 will also be equipped in this manner.
They are exploring ways to make the steam engines stand alone PTC equipped.
Jeff
Isn't this a moot question for the most part? Aside from UP, which of the class 1's operate or permit the operation of preserved steam on their track? I can see it being a problem for the tourist pikes that own their own track, the D&S, CATS, Straburg and (soon, I hope) EBT, etc. I can see them either being denied insurance or having their rates skyrocket if they are hauling passengers without PTC. Yes, yes, I >KNOW< they may be exempt, but we're talking insurance carriers, not the Feds. And to non-railroaders and non-railfans, it's the silver bullet that will prevent all accidents and injuries
There is a great potential danger in such a thing if applied to North American weights and speeds; consider the likely cause of the Gulf Curve wreck on NYC in 1940, caused by precisely this action with the normal throttle. What is needed, again, is a dashpot arrangement that smoothly and relatively gradually either cuts or wire-draws the steam to low pressure before completely cutting it off;
In the UK, of course the weight of the train was negligible, even compared to the small locomotive used.
The valves had levers with counterbalance weights to allow the vacuum cylinder to act in one direction only. A dashpot arrangement could be added to this counterbalance system.
Peter
There is an amusing anecdote in Cook's 'Swindon Steam' about how some of this was managed. Apparently in push mode the driver would close the throttle to simplify the fireman's winding up the reverser; the fireman would signal he was done with that with a 'toot' on the whistle. This led to so much whistling at logical places that there were complaints...
One would figure that a fairly simple form of engine-room telegraph that repeaters the cutoff indication would serve here.
M636CLater locomotives intended for push pull use, including some British Railways standard types, had vacuum actuated valves in the steam pipes between the throttle and the cylinders. This allowed the driver in the remote cab to cut locomotive power immediately in case of an emergency stop. A similar system (presumably air actuated) could simplify the installation of PTC in a steam locomotive.
I have argued in the past that a simple way (in theory) to implement this kind of 'soft' control comes when a locomotive is equipped with Porta's arrangement of four Wagner throttles (he called them "Waggoner" throttles in the ACE3000 patent) for low inline steam resistance. A variety of devices can safely modulate these even if brakes are applied from very high road speed (and hence high cyclic, very high inertia forces, and high back pressure/compression effects if a throttle is closed quickly)
With the advent of air throttles, as with the one applied to some PRR T1s (and specified for replica 5550), it becomes trivial to arrange a closed throttle independent of control position, without requiring 'intermediate members' in the valve-gear support.
In the United Kingdom, there was extensive use of "Push Pull" trains where a steam locomotive and often a single car were used on secondary lines. In one direction, the locomotive driver controlled the train from a driving cab in the passenger car.
Operation of the Vacuum brakes was straightforward but operation of the throttle was not. The fireman remained on the locomotive to tend the fire, operate the injector and possibly to open and close the throttle possibly on command from the driver using an electric bell signal.
However, this made stopping quickly a problem.
Later locomotives intended for push pull use, including some British Railways standard types, had vacuum actuated valves in the steam pipes between the throttle and the cylinders. This allowed the driver in the remote cab to cut locomotive power immediately in case of an emergency stop.
A similar system (presumably air actuated) could simplify the installation of PTC in a steam locomotive.
Thanks, that helps.
bogie_engineerIf a train hauled by a steam locomtive breaks in two, does the emergency brake application close the throttle as it does on a diesel? It seems that to install PTC on a steam loco would require such a device yet my mental picture of a steam throttle doesn't include any means to automate it. Do such devices exist?
A point to remember is that the initial enforcement in many of these systems was via 'penalty' ATS... and almost all the trains involved were steam-powered in the early 1920s.
We might note at this point that a consist with automatic and independent 'locked on' exerts many more 'horsepower' than locomotive cylinders can exert, so even in an "emergency with disabled engineer" the train would be stopped, either with the drivers physically stalled by the driver brake or with the drivers slipping. This is relatively crude, but repeated tests established it would be effective. If all the couplers and draft gear held, and the train did not separate.
The "best" way to handle this situation was to have a power reverse on the locomotive and an arrangement that centered this as part of what the ATC tripped. An alternative was some form of servo that would accomplish the same thing on a mechanical (or even Franklin Precision) type of in-cab control with proportional setting -- this doubling as a form of speed control enforcement if that were desired.
With the advent of air throttles, as with the one applied to some PRR T1s (and specified for replica 5550), it becomes trivial to arrange a closed throttle independent of control position, without requiring 'intermediate members' in the valve-gear support. Any of the air-throttle systems being sold for new construction or conversion in the late '40s (as documented in the contemporary trade press or the Locomotive Cyclopedias) like the ThrottleMaster would easily accommodate this.
For older power, the likeliest answer would be installation of a Wagner dome throttle of adequate size, with its control spool connected to the ATS apparatus. This would not interfere at all with steam flow through the Multiple front-end throttle, but could selectively modulate effective dry-pipe pressure as well as cut off saturated steam; the only issue would be that heavy priming carryover would still flash in the elements and sustain output for a few seconds.
Note the practical differences between relatively crude ATS and what a good modern PTC system does. In my opinion it would make sense to have servos on both the reverser and air throttle that could implement proper TVM-style 'cruise control' at any speed; a trivial amount of 'human-machine interface' equipment would make its action comprehensible to anyone in the cab.
BaltACDMy understanding is that PTC does not initiate Emergency Brake Applications, just maximum Service brake applications.
It can do both.
It's been fun. But it isn't much fun anymore. Signing off for now.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any
Remember - most carriers have equipped their locomotives - a train initiated emergency application doesn't trip the PC Switch for a number of seconds after the UDE is detected - the theory, I surmise, is for the part of the train coupled to the engines to out run the suspected rear part of the train that could run into the head part of the train and create a impact derailment within the body of the train. Engineers become the PC switch on steam locomotives using the experience, skill and judgement in safe operation of the train.
My understanding is that PTC does not initiate Emergency Brake Applications, just maximum Service brake applications.
Never too old to have a happy childhood!
This old thread doesn't discuss it, but since I know very little about steam locomotives I have to ask:
If a train hauled by a steam locomtive breaks in two, does the emergency brake application close the throttle as it does on a diesel?
It seems that to install PTC on a steam loco would require such a device yet my mental picture of a steam throttle doesn't include any means to automate it. Do such devices exist?
Dave
JDavidA103751 already has ATS. If that can be used for PTC, then all should be good.
1940's ATS is not 21st Century PTC.
jeffhergertNo, except you have the restricted speed hash box on the screen and if your speed goes over 22 mph, PTC takes your air. About the same as we're used to with the exCNW's ATC. Jeff
Same with our LSL. Although mine aren't big enough to do 22 on a restricting.
zugmann jeffhergert My employer is now requiring every engineer to have at least one stop test made under PTC restricted speed operating conditions every year. Any different from a banner test?
jeffhergert My employer is now requiring every engineer to have at least one stop test made under PTC restricted speed operating conditions every year.
Any different from a banner test?
No, except you have the restricted speed hash box on the screen and if your speed goes over 22 mph, PTC takes your air. About the same as we're used to with the exCNW's ATC.
jeffhergertMy employer is now requiring every engineer to have at least one stop test made under PTC restricted speed operating conditions every year.
The PRR ATC system in the NEC was in place and working through Amtrak, and was removed at the Frankfort curve only to permit easier installation of the new PTC system. Like the CSX-Amtrak passenger train into a freight on a siding situation, it is also case where the process of installation of PTC was the main contributor to the accident!
Sunnyland from what I hear thru FB friends who work on RR's etc, PTC will not be the end of all accidents, they might help, but many of the systems already in place should have too. From what I've heard PRR had a great system similiar to this and it was torn out many years ago when other RR's took over, it had been installed on the Philly line where the terrible wreck happened in 2015, but was no longer there.
from what I hear thru FB friends who work on RR's etc, PTC will not be the end of all accidents, they might help, but many of the systems already in place should have too. From what I've heard PRR had a great system similiar to this and it was torn out many years ago when other RR's took over, it had been installed on the Philly line where the terrible wreck happened in 2015, but was no longer there.
PTC won't prevent collisions when operating under restricted speed situations. My employer is now requiring every engineer to have at least one stop test made under PTC restricted speed operating conditions every year.
If PTC institutes a brake application in a diesel immediately behind a steam locomotive, the engnineer in the steam locomotive will certainly know it and immediately close the throttle, with brake application slowing or stopping the train.
Before we go too far about PTC as an unfunded safety mandate, consider that air brakes, (semi)automatic couplers and various safety appliances were eventually required by Federal statute.
You took the words right out of my mouth. The knee-jerk reaction is part of their aerobics-exercise program along with leaping to hasty conclusions, running around in circles and stabbing people in the back.
As stated earlier, PTC is not going to be installed on every single mainline in the U.S., there will still be plenty of secondary lines without PTC that could potentially host excursions. As I'm sure there are other ways around it as well, would just need to actually read the entire law/act to be sure.
zugmann Firelock76 Good point Zug, but remember the government let them have a way out. As I understand it long as the trains didn't travel faster than 79mph ATS didn't need to be installed. Give them an inch...
Firelock76 Good point Zug, but remember the government let them have a way out. As I understand it long as the trains didn't travel faster than 79mph ATS didn't need to be installed.
Give them an inch...
I can dig it. Money going out versus money coming in.
Firelock76Good point Zug, but remember the government let them have a way out. As I understand it long as the trains didn't travel faster than 79mph ATS didn't need to be installed.
Good point Zug, but remember the government let them have a way out. As I understand it long as the trains didn't travel faster than 79mph ATS didn't need to be installed.
Some 'roads installed it anyway, and good for them.
The thing is, I feel sorry for all those good people who put money, time, sweat, tears, probably some blood, and more than a little love into restoring their various steam locomotives, and who are about to have the rug yanked out from under them through no fault of their own. It just doesn't seem right.
PS: We like the Limestone Pie. Everyone else can just wonder what I'm talking about.
Firelock76Don't mean to offend anyone, and if I did I apologize, but I just had to say it.
But to play devil's advocate, cab signals and ATS have been around 100 years or so. Maybe if the railroads would have been more willing in pursuing technology on their own over the past few decades, the mandate wouldn't have been so forceful.
This could get me in trouble, but here goes....
I know we're not supposed to get political here. I know and understand that, it's a good rule established for good reasons. However there's something about PTC that just has to be said.
PTC was a governmental knee-jerk reaction to a wreck that was caused by an idiot motorman who was texting while he should have been paying attention to his work. By the way, how'd that dummy get the job anyway?
PTC was the result of a "SOMEBODY has to do something NOW!" mindset. No they don't, not until all the facts are in and the chances of a repeat occurrance are figured in. This is an example of the blind, heavy hand of government and pure panic legislation.
A better reaction would have been legislation on the state level providing for severe penalties for operators of public conveyances such as commuter trains, light rail, and buses, including fines and hard time, who operate said vehicles while impared or distracted. Regular medical physicals of said operators to reveal any health issues might have been added as well. Penalties for concealment of any known health issues could also be considered.
Many things can be handled adequately on the state level, the Feds don't have to be involved in everything, nor should they be.
So please everyone, take the lesson to heart. The next time "...they have to do SOMETHING..." crosses your mind, stop and think. One day "They" may come after something near-and-dear to your heart, as innocent and inocuous as it may seem.
Don't mean to offend anyone, and if I did I apologize, but I just had to say it.
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