Re: Hold Up a Moment
Because you can get blockages in the air line including someone closing the valves in the air line between cars. The first Fred's were just reporting. After a number of accidents where the air line was blocked the Feds mandated two way devices that could dump the air on the rear of the train from the head end.
When they first allowed cabooseless operations you only had to have a flashing red light or a red flag during daylight hours. A number of accidents put a stop to that including a runaway out of our terminal.