Originally Posted by phillyreading:
That's interesting about the Blue Flag rule! Also the first I ever heard of it.
Used to use track torpedoes to warn an oncoming train if a track was occupied. The device was a small powder charge that made a very loud & noticeable noise when run over and the engineer knew to stop his train, that was back when cabooses were still in use.
Lee F.
Lee,
The use of torpedoes was for main line, or siding, usage and was to warn that a train ahead had stopped, and MAY still be there. When running over two torpedoes, the Engineer quickly reduced speed to restricting (or below 20MPH), for two miles, being prepared to stop short of an obstruction or flagman. After two miles, and nothing encountered, you may resume authorized track speed.
The "Blue Flag" rule applies to yard or locomotive shop tracks, where personnel are working on, around, or under equipment. No torpedoes involved at all.