All of these pictures I took below were during the day. I need to look after dark even though I can't take pictures then. The devices light up only at night to save battery power. Reflective material that catches the locomotives headlight provides daytime warning. [Trains]
They are supposed to flash during the day if the brakes are applied. UP introduced EOTs in 1984.
The End-of-Train Device (ETD) transmits brake line air pressure and direction of movement every 40 seconds. "If there is a loss of radio continuity between the ETD and the cab, this will be displayed." A modern ETD is also required to receive a command to apply emergency braking (dump the air). [Trains] But the article doesn't say if a "hello" command is sent every 40 seconds from the front to the back so that the ETD can report the loss of communication to the ETD. We called a periodic "can you hear me now?" message the "heartbeat" protocol, and it was standard practice when designing communication protocols between computers.
They were originally called rear-end-devices. But workers added an adjective that expressed their displeasure with loosing the caboose thus giving us the acronym FRED. That adjective has since been sanitized as "flashing." Other acronyms this brings to mind is FUBAR (fouled up beyond all recognition) and RTFM (read the fine manual). I understand that FUBAR was invented by the military. I don't know which profession popularized RTFM, but it certainly applied to my profession of computer science. Actually, there were days when FUBAR was rather appropriate also. We had a saying: "it takes a computer to really mess things up."
I remember seeing red lights when they first replaced cabooses with EOTs. The red light indicated the end of a train like the marker lamps on a caboose.
|Library of Congress: Chicago, Illinois. Rear brakeman hanging out signal lamps on the caboose before a Chicago and Northwestern Railroad train pulls out|
The photo to the right is at camera resolution.
Some trains have a red flag instead of an EOT. I saw one on the end of a BNSF/CB&Q train that was being switched in Mendota and on an IHB train near the Burnham Ave. overpass. It seems if a train is going to go slow and the trip is short then it needs only a red flag.
|Scott Griffith posted|
FIRST EOT to arrive at BARR YARD
|Bill Molony posted|
Sorry, but I don't have a date or location for this photo.
Mick Swanson Totally novice here... what were cabooses used for?
Dennis DeBruler You have to imagine what railroading was like before diesel locomotives, radios, computers and dynamic brakes. Trains had a five person crew. The engineer, fireman, and head brakeman rode in the locomotive. (Although sometimes the head brakeman rode in a little shack at the rear of the tender.) The rear brakeman and conductor rode in the caboose. Without computers, the conductor used the caboose as an office because he had to process waybills. The brakemen ran on top of the freight cars setting and releasing the handbrakes. Even after air brakes were developed, the brakemen would have to partially set the handbrakes in mountains before going down a long descent. The crew in the back also monitored the air pressure in the airline. An EOT (End of Train) device used radio to allow the engineer to read the airline pressure at the end of the train. Going back in time before trackside signals were developed, if the train stopped, the rear brakeman would also have to grab a lantern and run a long distance behind the train to warn any oncoming train that there was a problem ahead. Of course, the fireman was busy monitoring the water level and stoker on a steam locomotive. In short, a train really did need a five man crew until about the middle of the 20th Century with two of them riding in the back.
Running Boards: https://industrialscenery.blogspot.com/.../missing-red...
Douglas B. Carlyle Mick Swanson great summary.
Jeff Lackman: Way bills were the instructions of where the cars in the train were being sent to or picked up from. In the day some trains made many stops to deliver and pick up freight cars from smaller factories and businesses than would be typical today (much of our freight now moves in containers and truck trailers which are moved in huge trains by railroads that deliver them at huge yards built just to handle trailers and containers).