Western Railroad Discussion > Help Please, What does "OS" mean

I here reference to the "OS" on the scanner frequently but have never been able to figure it what it means. Last night there was an extended conversation between the UP dispr and crew that had stopped in the "OS" and I guess the dispr was trying to talk him through the interlocking. What does "OS" mean? Thanks.

Old time term used during by telegraph operators and train dispatchers to indicated that a train has passed a particular location--"OS" means "on sheet" referring to the fact that the train dispatcher has recorded train movement on the train sheet he maintained each 24 hour period.

livesteamer Wrote:
OS" means "on
> sheet" referring to the fact that the train
> dispatcher has recorded train movement on the
> train sheet he maintained each 24 hour period.

Thanks Livesteamer!
I really never knew till now
what "OS" stands for.

Mark

On UP and BNSF, the area of track between opposing controlled signals, as in the end of a siding, is called an "OS Section". This is like a little electrical island. This can become quite large, such as the West end of Cheyenne at "Tower A", from the insulated joints under the familiar large west end signal bridge to the insulated joints at the various signals facing the other way on Mains P1, 2, 3 and 4 and the "Old way" and New way" yard access leads. - - - - - - -JLH

......well, don't remember where I heard it, but I thought it was "Out (of) Station"......

Bob

ATSF100WEST......Out

ATSF100WEST Wrote:
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> ......well, don't remember where I heard it, but I
> thought it was "Out (of) Station"......

There are many supposed definitions. Take your choice, since I never have heard a definitive one:

On Station
On Sheet (referring to the dispatcher's train sheet)
On Switch
Operating Statistics
and a couple more I can't remember

In this particular case, it is a signal term that refers to the track section between the opposing signals at an interlocking. The track circuit is called the OS track.

"OS" - "ON SHEET", recorded in the train
dispatchers journal or train
sheet.

Telegraph operators sent an "OS"
report to the dispatcher after
the markers on a passing train
left the station where the
operator was on duty.

On older signal installations, when
a train left a specific point, such as
the outer main switch of a major yard,
a bell rang to alert the dispatcher
that a train had left Rule 105
(dark) territory and entered ABS
(automatic block signal) territory.

That "clang" was sometimes audible
on the point to train radio, or on
the train phone.

Typically, there was a small relay
box beside the track to correspond
with the location that rang a bell
in the dispatchers office.

This bell was known as the "OS"
bell, and the dispatcher entered
the time that the bell sounded as
the leaving time of that train on
the large paper "train sheet" on
the desk in front of him/her.

Likely, even on newer signal systems,
the is a device or prompt which
highlights train departure time.

Dispatchers still think in terms of
time between stations as a guideline
for setting up meets etcetera.

In Amtrak, "OS" stands for operational status. This refers to a train's time status as to whether or not it is on time, ahead of sched (yes, it happens) or late.

"OS" translates "O scale". hehehehe
Or as it did with a train layout I built "Oh Sh!#"

RickH - having some fun aay?

highgreengraphics Wrote:
-------------------------------------------------------
> On UP and BNSF, the area of track between opposing
> controlled signals, as in the end of a siding, is
> called an "OS Section". This is like a little
> electrical island. This can become quite large,
> such as the West end of Cheyenne at "Tower A",
> from the insulated joints under the familiar large
> west end signal bridge to the insulated joints at
> the various signals facing the other way on Mains
> P1, 2, 3 and 4 and the "Old way" and New way" yard
> access leads. - - - - - - -JLH

This explanation seems to make the most sense in this context. It doesn't make must sense that a dispatcher would talk a train through the "On Sheet"

Yes, gee, and in addition to "all trackage" I forgot to specifically add "including switches", and/or crossovers between opposing controlled signals as the case may be. In this context "OS" stands for "on station", as theoretically each one of these "OS" sections is a seperate "station" location. - - - - JLH

My defintion of "on sheet" comes from my granddad's 45+ years as a train dispatcher on the Lackawanna. He used a telegraph key, company phones and train sheets to run a railroad from Hoboken to Denville on the old Lackawanna.

During the time I worked for a RR, I always unstood the term 'OS' to mean 'On Sheet'. If you look in older RR timetables, you'll see a two letter abbreviation for a station name. That's the abbreviation (short hand) the telegrapher used to communicate that name to the dispatcher since the telegrapher used Morse code in the early days. In places where they still use Morse code (like ham radio) they still use abbreviations to make it easier to send the message in Morse code. Morse code is slowly disappearing from use most everywhere, including ham radio, but it is still the only form of communication approved on almost every kind of radio communications... That's why you frequently hear morse code on police channels, and railroad PBX freqs, to identify that particular transmitter.

Really, I always thought that it meant "open switch", and this picture would help me out.
TacDen at Longs Peak, CO, on October 15. Train has BNSF 732 and a NS SD50(or 60).
~wko

---

Thanks everyone for your responses. I think highgreengraphics has the definition that's most applicable here. So, if you were asking for track & time, as I understand highgreengraphics definition, and wanted only the "OS," you would say something like, "Control point B003, not including the switch to Control Point B004, not including the switch."

Another interpretation...'out of station' used to release section of track so that it can be given to someone else. Heard this years ago and it's interesting to hear of other's understandings of the term. Best wishes.

WichitaJct Wrote:
-------------------------------------------------------
> Thanks everyone for your responses. I think
> highgreengraphics has the definition that's most
> applicable here. So, if you were asking for track
> & time, as I understand highgreengraphics
> definition, and wanted only the "OS," you would
> say something like, "Control point B003, not
> including the switch to Control Point B004, not
> including the switch."

Think you guys ought to ask a dispatcher (I am not one). In today's computer track venacular I think dispatchers use the OS term for "occupied section." A dispatcher may not be able to line or give a signal to a train to enter the next circuit or block because he shows an "occupy" on his computer screen. It could be a broken bond wire, broken rail, God-forbid another train overshot his red signal, most anything shorting out his circuit; hence, as far as he knows, the block is "occupied" by something.

This is one explination that depends on your era. All the references to "On Sheet" would have been correct in the proper era. I think the Amtrak info does not apply to this discussion. There is some overlap between CTC and tower operators. However the context here is about CTC setups.

Today the OS circuit is in all CTC setups and is not specific to a railroad. The OS is WITHIN a control point -- between signals of a given location. It is somewhat different from track being occuiped. With the OS circuit occupied no changes to signals or switches can be made with in the interlocking.

The OS is a very specific area occupied and track occupancy involves a longer section of track.

DS need trains to clear the OS otherwise the interlocking is locked up.