No, I don’t really know the answer to this one. It may be a cost / benefit calculation given that sidings have a higher density of hand-throw switches, and that it’s still going to be safer to install CTC on that low-speed siding than to leave it “uncontrolled” (see below).
Traditionally, under T & TO operation, sidings were not under the dispatcher’s control, i.e. a train didn’t need to have any authority to be on a siding. The same is still true today in track warrant territory. But in CTC, sidings are usually operated just like the main track. Trains get authority to enter the siding from the controlled signals at either end; or, if they’re entering via a hand-throw switch in the middle of the siding, they have to get verbal authority from the dispatcher.
The same rules apply to maintenance-of-way work groups. To work on a siding in track warranty territory, they must set up derails or line and lock switches away from their route, whereas in CTC territory they would need to get an autority from the dispatcher.
So generally speaking, a siding in CTC territory is “controlled siding”, while a siding in track warranty territory is not.
However, the rules books tend to use the phrase “controlled siding” rather than “CTC siding”. I assume this is because it’s always possible for the division timetable to designate a CTC siding to be uncontrolled, or for a track warrant siding to be controlled.
In the original ETMS (the predecessor to the PTC system used by all the big freight railroads), which was
I would opine that a controlled siding would be one that will be in regular use for things like meets and passes, whereas an uncontrolled siding would be one used to access industries, etc.
Here is the definition of a controlled siding from NORAC. I suspect GCOR and Canadian rule books have similar defintions:
CONTROLLED SIDING (CS): A circuited siding in which both ends are controlled and governed by signals under the control of a Dispatcher or Operator.
If the siding is “circuited”, I expect that means the dispatcher can see when the siding is occupied by equipment that can shunt the track circuit. An industry siding is unlikely to be circuited, and so once a train goes on one, it disappears off the dispatchers “radar”. But whatever switch allows the train out of the uncontrolled siding and back onto controlled track will need to be tied into whatever signalling system exists. It is at those locations where I imagine the switch timers most often come into play.
Yes. I’m not sure when the change happened. Probably around the time the UCOR was replaced with the CROR.
The RTC will almost certainly face severe discipline, but may or may not be dismissed. This sort of error is akin to a train crew passing a stop signal or otherwise occupying the main track without proper authority. These offences normally warrant a lengthy suspension and/or a lot of demerits, but whether or not you get fired depends on the particulars of the individual incident.
We have a variation called Siding Control Territory in Canada, where the siding itself is dark (unbonded) but has power switches and signals at both ends. The siding is to be considered “known to be clear” unless told otherwise, so trains can head in at the permissible speed (usually 15 or 25 mph) without needing to comply with the requirements of reduced or restricted speed.
Verbal permission from the RTC is all that is required to occupy a SCT siding if you are entering somewhere along it, such as from a spur or a foreman putting on at a crossing.
This arrangement also allows one train to follow another into the siding on signal indication without needing to copy a pass stop authority, in this case the RTC is required to inform the second train that the siding is not clear before requesting the signal into the siding.
But I don’t get why it’s okay for a train in a controlled siding to go twice as fast as the train on the main? Could you give an example that illustrates why this is.
No, I don’t really know the answer to this one. It may be a cost / benefit calculation given that sidings have a higher density of hand-throw switches, and that it’s still going to be safer to install CTC on that low-speed siding than to leave it “uncontrolled” (see below).
Lithonia Operator
And what is a controlled siding? Any siding entered by a remotely-controlled switch?
Traditionally, under T & TO operation, sidings were not under the dispatcher’s control, i.e. a train didn’t need to have any authority to be on a siding. The same is still true today in track warrant territory. But in CTC, sidings are usually operated just like the main track. Trains get authority to enter the siding from the controlled signals at either end; or, if they’re entering via a hand-throw switch in the middle of the siding, they have to get verbal authority from the dispatcher.
The same rules apply to maintenance-of-way work groups. To work on a siding in track warranty territory, they must set up derails or line and lock switches away from their route, whereas in CTC territory they would need to get an autority from the dispatcher.
So generally speaking, a siding in CTC territory is “controlled siding”, while a siding in track warranty territory
I would expect that a lot of delayed in block trains would be oversized loads. Observed one the other day doing just about 5 MPH with a 32 axel load. Also could MOW equipment also be delayed in block ?
Jeff - you corrected two things I said wrong (the speeds at which electric locks are required, and the DIB rule). Thanks you for that. I corrected my previous post.
Most MOW equipment does not operate on signal indications, most smaller equipment will not reliably shunt track circuits and a lot of equipment has insulated wheels/axles so they cannot activate crossings or the signal system.
Such equipment normally operates under written work authorities from the RTC, in Canada it’s called a Track Occupancy Permit (TOP) in CTC territory.
Delayed in the block would more likely apply to trains that have stopped to perform switching or due to an emergency brake application (perhaps caused by a train separation).
A speed restricted movement handling a dimensional load would easily be able to comply with this particular rule.
No. MOW equipment isn’t governed by signal indications.
Delayed in the Block happens when the speed drops below 10 mph. The GCOR rule number is 9.9, which is any easy way to remember it. If your speed drops to 9.9, you’re delayed in the block.
If you are in continuous cab signal territory, you’re never delayed in the block, even if you stop. The cab signal indicates the condition of the block you are in.
Sometimes MOW equipment moves as a train, using signal indications or “proceed from” track warrants. An example would be things like the Herzog MPM, which in travel mode can move at normal train speeds. But your typical on-track equipment gets special verbal authorities in CTC territory and interlockings, and “work between” warrants in track warranty territory. It must always be prepared to stop in half the range of vision, and must approach every road crossing prepared to yield to road traffic. These movements are made without any regard to the wayside signals, so DIB is not an issue. Aso: the signal system doesn’t protect work equipment. Even in CTC a single dispatcher error CAN lead to a train v. MOW collision all by itself.
And to oversimplify things a bit: just like certain kinds of work equipment sometimes move as trains, work trains sometimes move as if they were work equipment.
DIB was raised to a issue in the MARC vs. Capitol Limited collision at control point Georgetown Jct near Silver Spring, MD on February 16, 1996.
In the preceeding months CSX had performed a signal respacing project along the Metropolitan Sub to improve safety with the size freight trains that were being operated on the territory. A Eastbound MARC commuter train after accepting a ‘Approach’ signal indication made a station stop to pick up/discharge passengers. The engineer on the MARC train (that was being operated in push mode) left the station stop as if he had a Clear signal upon entering the station. The MARC train accelerated toward track speed and came around the curve at Georgetown Jct. to see Amtrak P029 crossing over from #2 track to #1 track ahead and the Absolute signal for the control point displaying STOP. 8 dead on the MARC train.
Afterwards, the FRA came out with enhanced Delay In Block regulations that included passenger trains making scheduled station stops.
MofW Equipment operates on track authorities - they DO NOT operate on signal indication.
VIA had a similar crash in 2012. As the entire head end crew was killed and the locomotive was not equipped with any cameras there is no absolute proof of what actually went on in the cab and what signals the crew saw (or thought they saw), but the most likely explanation based on available evidence is that they forgot what signal indication they came in on before making a station stop, and thought they would be routed down a straight main track (like normal) instead of through a 15 mph turnout.
As it turned out this incident eventually led to inward-facing cameras and cab voice recorders becoming legal in Canada, with the railway companies having access to the footage and recordings.
Didn’t the FRA after this accident require any passenger train leaving a station to operate at restricted speeds until next signal is passed and operate at that signal’s aspect ? Or is it until next signal
That is what the Delayed In Block is all about. Leave scheduled station stop at a speed that will permit stopping at next signal - until such signal is observed and is displaying a indication other than STOP.
In SOME station locations, signals are being placed right where the engine would be after the train makes its scheduled stop - the NEXT signal is in immediate view.