pierson@kirk.DEC (02/17/86)
This is my first time out (if I get there). In response to the questions
raised by the VIA/CN Wreck. Generally freights do not run to timetable,
but EVERYBODY is supposed to be governed by the block signals, unless given
permission by them. As noted elsewhere Diesel electrics inherited the
deadman control from straight electrics. Contined pressure on the throttle
or a pedal being required. Note that this is typically down on the throttle
and is not related to throttle positiion. The Pedal can be beaten, see the
"Silver Streak" movie.
A more sophisticated system requires continual motion by the operator,
typically with a 3 minute time out. The one installation I know of is in
Australia, where there is a stretch of dead straight, level track ~500 Miles
long.
The Railroad analog of the rapid transit tripper is used with cab
signals. If the train runs past a "more restricting" indication, above a
defined speed, first a whistle sounds, then the brakes go into emergency.
Pennsy used tripper Automatic Train Stop in the Penn Station tunnels.
Dave Pierson
(DEC E-NET) Kirk::pierson
(UUCP) {decvax, ucbvax, allegra}!decwrl!dec-rhea!dec-kirk!pierson
(ARPA) pierson%kirk.DEC@decwrl.ARPA