Jump to content

英文维基 | 中文维基 | 日文维基 | 草榴社区

Talk:Lathen train collision

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia

Needs more detail

[edit]

Did the driver of the train see the maintenance vehicle and attempt to stop? If so, was he unable to stop due to the train's high speed? How quickly can a maglev train stop at various speeds and is this faster or slower than a conventional train?... Many articles have said or implied that since the accident was due to "human error" there is nothing fundamentally unsafe about the technology. But if the thing moves too fast for a human operator to respond to a threat, maybe that is a problem with the technology. This and related questions should be discussed. JDG 00:38, 30 September 2006 (UTC)[reply]

The details in the crash report (in the article) say that the brakes were applied approximately half a second before collision, and that the impact was at 162km/h (presumably there was a data recorder onboard). If we assume it was travelling at the expected 170km/h immediately beforehand (something that would have required about twice the normal acceleration of a steel-rail train - as the collision happened less than a minute after starting off - but entirely within the abilities of maglev), that implies braking power of about 16km/h per second (again 2 to 4 times the emergency braking performance of most normal trains). Thus it has much better acceleration and braking performance than a conventional railroad train, and could have come to a complete halt in less than 11 seconds, or about what a car might need to stop from that speed on a wet road with good tyres - massively reducing the total braking distance. It's also stated that the train covered approximately 25m in that time, or about 48m/s (as it was, more exactly, 0.52s), which works out to about 173km/h (and an anticipated stopping distance of only about 264m)... it doesn't all add up exactly, but the variation is under 2%, which is pretty good for speeds and distances listed in wikipedia articles ;)
Therefore there's nothing particularly risky in the running speeds, or speed-control performance of the maglev itself, given that it easily outperforms conventional rail systems that achieve similar speeds (including HSTs that operate at 350km/h or more, with advanced braking systems that augment what steel wheels on steel rails could normally produce). Nor is it entirely unusual for sight distances on rail lines to be considerably below (or speeds considerably above) what would be required for safe operation reliant entirely on driver vigilance - that's the entire reason for the various systems of signalling, token based block working, timetabled operations, switch interlocking, etc that have proliferated throughout the near 200 year history of railroading, and why lines are usually fenced off and have systems to reduce potential conflict between trains and passengers at stations or other vehicles at grade crossings, and why any cases of road running, including light but especially heavy rail, come with extremely low speed limits.
Without those techniques, rail transport would only be possible with quite low speeds (not much above modern "extreme caution" speeds used for permissive passing of danger signals), running equipment made with much more effective braking abilities (likely with a corresponding reduction in efficiency and passenger comfort), track alignments planned even more carefully than at present to ensure as long-as-possible sightlines, and the absolute bare minimum of single tracking, grade crossings and at-grade switches that include the use of frogs (rather than bridges or underpasses) for double track diverges. Or in other words, the same combination of stationary maintenance vehicle, fast moving train, track alignment requirements and signal control mistakes would have had at least as catastrophic a result if not quite a lot worse (as there would have been derailment, jackknifing, blocking of any adjoining lines, and likely greater damage to both vehicles as they're further off the track and generally not as strongly built).
The extremely short reaction time does seem unusual, particularly as one wouldn't think that an elevated track like this would have particular issues with visibility and sightlines because of the lack of environmental obstructions. However, the increased inherent safety of the system might have led to reduced driver vigilance (they may well have been turned round talking to passengers, having assumed there was literally nothing else on the line that they could possibly hit and that it would be a minute or two before they would need to make any further control input after levelling out at 170k - then hit the brake after turning round to see what a panicked passenger was pointing at), and the much more positive application of cornering force and increased ability to apply forward thrust or braking would allow rather tighter turns and vertical slopes and curvature even at high speed, reducing the lead time in terms of being able to see unexpected obstructions even with otherwise good visibility. There may also e.g. be dividing walls between adjacent tracks to reduce slipstream buffeting where the lines are required to run close together (two trains passing at 450km/h each would produce winds equivalent to a passenger jet passing at normal cruising speed... a mere few metres away), which would cause visual obstruction, or the line may curve around tall buildings, steep cliffs... run through lengths of tunnel... etc.
Essentially, the reason for the incident is listed in the article - a breakdown in proper signalling and dispatching procedures. For some reason the maintenance vehicle didn't show up as a train occupying a section of the maglev track as might be expected (same as an equivalent vehicle would automatically trigger trackside signals and show up on a signalhouse line map as an occupied section with a normal railway), and the dispatcher responsible for clearing the maglev for departure (either through light/cab signals, or over line radio), onto what the driver would then have thought to be a completely empty line, failed in their duty to be mindful of the maintenance staff - who occupied the line for the same period of time every day - even though the maglev run was taking place half an hour earlier, and registering the line as clear was an active process involving two-way radio communication between the workers and dispatch (rather necessary, in case they found a fault with the line, or their maintenance truck broke down and couldn't be moved from the line, etc) and the switching of line points (a rather more heavy duty thing for maglevs than normal rail, as an entire section has to be rotated between two configurations) so they can actually leave the line onto a siding anyway.
Thus the root cause of the crash was something that could have happened on any railway, including one running at half the speed or less on normal rails - a combination of poorly set up safety systems, a patchy procedure put in place to compensate for that, and a crass failure of the signalling staff (who have a prime responsibility for maintaining system safety) to do their job. Human error, if you want to put it that way. Nothing to do with the monorail being inherently dangerous, regardless of what The Simpsons might suggest. 209.93.141.17 (talk) 17:46, 15 September 2017 (UTC)[reply]
It was a driverless train. I have edited the article to make that clear.--Shantavira 13:18, 17 November 2006 (UTC)[reply]
The Transrapid trains are not driverless. The driver of this particular train was killed in the cockpit.
I'm removing the cleanup tag as the article looks fine to me in that department. If it needs more detail, then expansion request is the tag needed. --Wolf530 14:41, 29 October 2006 (UTC)[reply]
Some of the information here conflicts with that in the Transrapid article. Or maybe it just depends what one means by a train that doesn't run or rails becoming "derailed". So did it or didn't it? --Shantavira 13:18, 17 November 2006 (UTC)[reply]
Although it doesn't run on the rails, it is still "wrapped" around the rails. Thus it is theoreticaly possible to derail. But it didn't in this case, because being wrapped round without touching as it is, it is almost inconceivable unless a section of elevated track were to collapse... Blood red sandman 18:03, 17 November 2006 (UTC)[reply]

Feet or Meters?

[edit]

The section Firefighters used turntable ladders and aerial platforms to reach the wreckage, which was at an elevation of four feet. seems incorrect, as it appears much higher in the pictures. The BBC link in the page also says Damaged carriages were left balancing on track 5m (16ft) in the air, hampering rescue efforts. So either it's 4 meters, or forty feet. Identity0 09:25, 27 March 2007 (UTC)[reply]


Article Naming: February 2009

[edit]

This page was recently renamed by someone who has been permanently banned; he was mistaken about naming conventions. Please see the naming convention for disasters, that states that all articles concerning individual disasters should be <<year>> <<place>> <<event>>. Also, it is recommended that discussion & consensus should occur before any pages are moved. I'll move this back if there is no objection. Highspeed (talk) 05:30, 26 February 2009 (UTC)[reply]

No objections noted. Done. Highspeed (talk) 02:56, 4 April 2009 (UTC)[reply]

Messed up first paragraph: March 25, 2009

[edit]

The first paragraph of this article appears to be messed up, with an obviously incorrect number of fatalities and some visible tags. I don't know the actual number of fatalities or I'd fix it myself. —Preceding unsigned comment added by 69.50.96.66 (talk) 15:59, 25 March 2009 (UTC)[reply]

 Done Vandalism repaired Blood Red Sandman (Talk) (Contribs) 18:41, 25 March 2009 (UTC)[reply]
[edit]

During several automated bot runs the following external link was found to be unavailable. Please check if the link is in fact down and fix or remove it in that case!

--JeffGBot (talk) 04:50, 14 June 2011 (UTC)[reply]

Crash details unclear - suggestions for improvement

[edit]
map of the test tracks

As I read the article, I'm having difficulty imagining exactly how the accident happened - the logistics, if you will.
1: Perhaps the map/diagram from the Emsland test track article (this one) can be updated to include location of the depot side-track, location of the crash and direction of the two vehicles.
2: "When these works are finished, it has to wait before the last turnout". This is very unclear. There is a turnout at each end of the loop and one at the depot in the southern end of the straight section. Which part of track was the maintenance vehicle supposed to have stopped at, and where did the accident happen?
3: Had the MV already finished work and headed back, in progress, or just heading out on the track, where the train was already running/located?
(4: I have expanded a sentence on the article, to include that there is also a depot.)

If anyone have read the official report or later news, perhaps explain this question in the article:
5: If the MV was in one of the loops (or had "waited before the last turnout"), would the train still have hit the MV?
-- Katana (talk) 21:02, 10 February 2016 (UTC)[reply]

There is now a schematic map of the test tracks (added to this section now). The maintainance vehicle had finished and it was waiting at the turnout ("Weiche") to the depot ("Versuchszentrum"). Technically it was at pile 120. The workers moved to the rear of the vehicle - so they could not see the platform ("Besucherzentrum") where the people were boarding the train. When the tracks were energized the train driver and station director would have been able to see the vehicle. In don't know if the train had first run through the small loop - I guess so. Guidod (talk) 10:43, 21 February 2016 (UTC)[reply]

Missing statistic

[edit]

Most, if not all (!), accident articles include passenger counts. Then as one sees the victim counts one can get an impression of how destructive the unfortunate incident was. Here, I couldn't find the passenger count for the train. Only the passenger count for the maintenance vehicle is listed: 2. Of which 2 survived.

Now, the train passenger count is implied, as deep down the article it says that no-one survived unscathed. So if one adds the fatalities + the injured, and assuming the "no unscathed" sentence is accurate, one can guesstimate the passenger count (but does that include the 2 maintenance vehicle workers?).

The way this article is written is all so very strange and alien to the way most accident articles are. No wonder the sections above claiming for additional clarity! XavierItzm (talk) 13:48, 15 June 2022 (UTC)[reply]