Just curious.....in the old days, whenever a train made an unscheduled stop with the danger of being overtaken by another train, there were procedures required to signal an approaching train. Under the old "rule 99", a flagman might have to place 2 torpedoes (explosive noisemakers which detonated under approaching wheels) and, when necessary, signal via a lighted fuse or red flag, to warn the oncoming train.
How do Amtrak and freight railroads do it today? Is it all by radio communication, or is some sort of flagging/lighted fuse signal also necessary?
Richard
Posted by Henry Kisor (Member # 4776) on :
Hey, this is a good question -- isn't there someone with operations knowledge here who can answer it?
Posted by rresor (Member # 128) on :
No more flagging, and no more torpedoes. Torpedoes passed out of general use when cabooses were discontinued a decade or more ago. Flagging was obviated by the move to radio-issued "track warrants" or "direct traffic control". Both work much the same way. The dispatcher grants exclusive occupancy of defined limits to a train (in DTC, the blocks have set boundaries, in TWC the segment is defined by mileposts). TWC does allow for following movements in the same block, but with an instruction to "look out for Train #__", with a requirement to proceed at restricted speed.
Work limits for track gangs are granted in essentially the same way. They can either be an absolute block, or have a provision that trains can contact the foreman in charge and request permission through the limits.
I'm sure anybody who is a dispatcher can amplify this and correct any misstatements I might have made. I know this stuff only from having observed it during cab rides, hi-railing, and working on the track.
Posted by Geoff M (Member # 153) on :
Only other thing I can add is that if the train is delayed in section for a time, it should approach the next signal at reduced speed (prepared to stop?) until the aspect can be determined.
I can't find specific references to this rule so it may not apply nationally or may indeed be partially or wholy wrong.
Geoff M.
Posted by rresor (Member # 128) on :
Geoff M.: That's the "delay in block" rule promulgated by FRA after the collision of a MARC train with Amtrak's "Capitol Ltd" in Maryland.
Rule says that, if a train comes to a stop for any reason between block signals, it must proceed at restricted speed until the aspect of the next block signal can be observed.
That's really independent of any flagging rule, though.
Posted by Geoff M (Member # 153) on :
Thanks for that rresor; my reply was triggered by yukon11's "made an unscheduled stop" comment.