Trains calling "clear by telemetry" on Worcester Branch

Often I hear trains (usually SEPO)call D3 on the radio that they are "clear of MPX 25 by telemetry." Does the EOT device have GPS that gives the crew the location? Why do they need to inform the dispatcher in this manner, doesn't he get an indication when a train is clear? And it seems they call when they are close to CPF 312 where the rear of the train would seem to be well clear of MPX 25 which is on the far end of the Hill Yard. Thanks in advance for any replies.

neman2 wrote:Often I hear trains (usually SEPO)call D3 on the radio that they are "clear of MPX 25 by telemetry." Does the EOT device have GPS that gives the crew the location? Why do they need to inform the dispatcher in this manner, doesn't he get an indication when a train is clear? And it seems they call when they are close to CPF 312 where the rear of the train would seem to be well clear of MPX 25 which is on the far end of the Hill Yard. Thanks in advance for any replies.

Worcester "Main" is DCS territory, which is another way of saying it's dark territory and the dispatcher can't see what's moving over it. Trains calling clear by telemetry have a working marker being received by the head end of the train, and the head end is a specified number of miles beyond the point they're calling clear of.

FYI here is the entire norac rule for calling clear of DCS.

because mpx25 through the hill yard to AY is non controlled track there are no mileposts so none of that counts. They could call it earlier than 312 but that's a safe distance.


Trains may be reported clear of DCS territory or intermediate points only after an
employee has determined that the rear car has cleared by one of the following means:
1. Observing the marker.
2. Observing the last car number.
3. Observing the telemetry device indication on the head end to ensure that air
pressure indicates brake pipe continuity, once the head end of the train is 3
miles beyond the clearing point.
4. Receiving a correct axle count from an equipment defect detector. This method
may be used only when the axle count from the detector agrees with the count
of a previous detector or with an actual axle count made by a crew member.
5. Receiving data from an Automatic Equipment Identification (AEI) reader that
correctly identifies the last car number or marker number of the train.

On NS, I think crews also use a reset-able distance counter in the locomotive in conjunction with a good telemetry reading to know when a train such as the often 8,000+ ft 22K has cleared the Southern Tier main onto the Buffalo running track in Binghamton.

Where are CPF and MPX numbers measured from? Do they date back to New Haven usage?

BandA wrote:Where are CPF and MPX numbers measured from? Do they date back to New Haven usage?

CPF ("Freight main") milepost numbering was created by Guilford and starts at Mattawamkeag, ME. I'm guessing that mileposts on the Worcester branch are the distance from Worcester as this line was built by the Worcester, Nashua, and Portland RR but this may be wrong...

johnpbarlow wrote:

BandA wrote:Where are CPF and MPX numbers measured from? Do they date back to New Haven usage?

CPF ("Freight main") milepost numbering was created by Guilford and starts at Mattawamkeag, ME. I'm guessing that mileposts on the Worcester branch are the distance from Worcester as this line was built by the Worcester, Nashua, and Portland RR but this may be wrong...

You are correct - MP 0 is located at Worcester Union Station. Also, just to correct a frequent mis-statement, there was no actual Worcester, Nashua, & Portland Railroad; it was the Worcester & Nashua, which was then joined with a couple of other railroads under B&M ownership into the Worcester, Nashua, & Portland Division (of the B&M). Also, there is no former NH usage involved - the route is all ex-B&M heritage. The NH ended at Worcester.

It's confusing with the P&W having bought the B&M line but PanAM still has trackage rights. There are three railroad names on Worcester Union Station, one of which is B&M. But only two "sets" of tracks.

Also, calling clear of a milepost or such may ne on the train orders. This could allow the dispatcher to dispatch another train in on those tracks.

History would show that there were 3 RR's at Worcester Union Station: NH(nee P&W),B&M,and NYC(B&A).
Now you have CSX,P&W,and PAR(via trackage rights) that are freight only,with Amtrak,with MBTA handling passengers only,

I think that the 3 mile requirement in NORAC is a little much. I usually let the counter go past the train length, a few hundred feet,, to account for any counter inaccuracy (which should have been tested in a measured mile), and for stretched slack. CP gives a +3% train length on the consists, to be sure the train has passed the point, which the movement is to call clear of.

Lots of things in NORAC are excessive, like DIB and having to run restricted all the way to the next signal. Not like GCOR where you can crank it up to the next signal prepared to stop.

The GCOR rule you quoted is in CTC only. ABS is restricted speed until the next signal is seen to display a favorable indication, and the track is also seen to be clear between the present location, and the next governing signal.

We (Pan Am) never ran in any weird GCOR Train Order/ABS territor like up on the MEC. Straight CTC... never paid attention lol.