It seems the older trains get, the more derailments there are. I think there could be a small vehicle that travels in front of the train. The distance in front of the train would be the same distance the train needs to stop. This vehicle could send electronic data to the engineer reporting upcoming track conditions. If any bad reports come in, there's just enough time to stop!
-- tj2010, Nov 20 2002

its not the trains. its the spads ( signals passed at danger), defective signals, defective tracks, lack of funding, breakup of british rail and defective drivers, who mostly wrongly, get all the blame etc...
-- po, Nov 20 2002


A train has quite a large stopping distance, which increases with poor conditions; the infamous 'leaves on the line' adds half a mile to the distance. Your 'small vehicle' would need to be a looong way ahead.
-- angel, Nov 21 2002


I like it, but maybe the _driver_ could travel in the small car and leave the train a safe distance behind. He would control everything by radio. There would of course be a backup guy in the engine, mainly just a brake-puller and guard should the train lose contact with the driver. The driver would essentially be doing, via remote control, what could be done remotely from a central station except that the driver in a little lead car would have a feel for the situation that no guy in the station would have.

And even though it take a long time to stop a train, it wouldn't take a long time to stop (or at least slow) the lead car, which would prevent a lot of collisions. The lead car would have to be far enough ahead to turn on the sirens and flashing lights, get people off the track, and then speed up again to avoid being rearended by the main train. If a collision was unavoidable, at least the main train would be moving more slowly and the people on the track (driver of stalled truck or whatever) would be saved.
-- horripilation, Nov 21 2002


There are, of course, many variables, but a train travelling at around 60 mph takes about a mile to stop, assuming good conditions, so your lead car would need to be at least that far ahead. Allowing for faster, heavier trains and less than optimal conditions, you should probably double that.
Of course, we're talking here as though this idea would be applied to trains in current use; if it were to be a feature of future designs, these objections may not apply.
-- angel, Nov 21 2002


Brilliant idea. Makes the effective length of the train into the length of the train plus the distance it needs to stop. I'm imagining a head on between these two things: The two bumpers smash themselves to bits at a combined speed of 250mph, both trains perform emergency stops and come to a halt just a few meters apart. Übercroissant.
-- st3f, Nov 21 2002


Excellent idea! With modern communication the little car could be as far as you would need it to be ahead of the main train. Could possibly save alot of lives or cargo.
-- jonesin143, Nov 21 2002


Yep. This is nice. I imagine it as a small, telemetry equipped, unit that rides upon just one rail, carefully modulating its foreshadow distance depending on train speed and conditions. Maybe relaying video back to the engineers as well?

One question, though: would the rail crossing be kept active/closed between the lookout unit and the train?
-- bristolz, Nov 21 2002


I see a problem: railway crossings. As it is the freight trains take forever (at least here in Vancouver) so now we're going to have to wait while the train bumper travels a mile or so in advance?
-- rbl, Nov 21 2002


Since the distance between the lookout unit and the train is speed dependant wouldn't the time the crossing be active/closed be constant or nearly so?
-- bristolz, Nov 21 2002


BZ, I'm not sure I follow, the freight trains go through the crossing at about 50 MPH. So if it takes the train 1 mile to stop at that speed the bumper needs to be 1 mile out in front, effectively extending the train length (and therefore my wait time) by 1 mile? Or did I miss something? At least it wouldn't be necessary while the damn things are shunting.
-- rbl, Nov 21 2002


No, [rbl], you didn't miss anything. I did.
-- bristolz, Nov 22 2002


Actually, 97.3% of train de-railments are actually caused by people trying to squash currency on the track.

Please Note: this figure may be highly incorrect, or just made up...
-- Supercruiser, Nov 22 2002


Excellent job for your first idea on the bakery, tj2010. Welcome. (WTAGIPBAN) +
-- krelnik, Nov 22 2002


If the train needs 1 mile to stop then the bumper would only need to be 1 mile ahead. The bumper could signal the railway crossings to close just before it would pass. If it takes the distance between the bumper and the train to stop the train shouldn't the crossings be down at this point anyway?
-- jonesin143, Nov 23 2002


Yes, but... Wheras previously you needed to leave a gap for the stopping distance of the train, now you need also to leave a additional stopping distance for the mobile bumper, too. Unless you intend having a good many minor accidents or a 'we stop for no-one' policy.
-- st3f, Nov 23 2002


The bumper could be compact enough that it would only take a few yards to stop in the worst conditions. This doesn't have to be another train itself, just a small vehicle, or two small vehicles (one on each track) sending track information and conditions back to the train.
-- jonesin143, Nov 23 2002


So, [Rod's] if there's a head on collision between two trains, at least subsequent trains know to stop? Doesn't that completely negate the original idea? Which, IMHO is a bloody good one and gets my vote.
-- egbert, Nov 23 2002


BC Rail does this. They send a hy-rail truck about a mile ahead of the train to scout for rockfalls.

Sooo. It's baked. But a good idea. :)

+
-- rapid transit, Jul 02 2003


This device would need to be a couple of miles long because that is how long it takes to stop a train.
-- jeffman, Jul 24 2003


Umm, yeah, I said that, way up there ---^
-- angel, Jul 24 2003


This is probably the best, serious idea I have ever seen on this site. (+) I only wish I could give it more croissants, and why have I never seen it before now?
-- silverstormer, Jul 24 2003


Nice idea. Works well on uncrowded, long sections of track. Would not work in britain, the bumper truck would be late, possibly meaning it's behind the train. Also congested junctions could get confused sending the bumper for the Paddington-Bristol train up to Derby... but [+] anyway. Would have prevented at least 2 of the recent fatal train accidents.
-- Jim'll Break It, Apr 11 2005



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