Message boards :
Cafe SETI :
train safety
Message board moderation
Previous · 1 · 2 · 3 · 4 · 5 · 6 · 7 . . . 11 · Next
Author | Message |
---|---|
rob smith Send message Joined: 7 Mar 03 Posts: 22149 Credit: 416,307,556 RAC: 380 |
Sorry Vic, I was looking at your post in the context of the crash in Spain, not a speed record by a highly modified train operating on a closed, very well laid railway.... Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 65689 Credit: 55,293,173 RAC: 49 |
Sorry Vic, I was looking at your post in the context of the crash in Spain, not a speed record by a highly modified train operating on a closed, very well laid railway.... Please read the article Rob in My last post, it's not a closed loop(if that's what you meant) and it's a research prototype that had a few cars left out. The T1 Trust, PRR T1 Class 4-4-4-4 #5550, 1 of America's First HST's |
rob smith Send message Joined: 7 Mar 03 Posts: 22149 Credit: 416,307,556 RAC: 380 |
Sorry Vic, I know a lot more about that train than that article says, mainly because I was involved in its control system design and modification for that run. (Sadly I didn't get a seat on the train) Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
tullio Send message Joined: 9 Apr 04 Posts: 8797 Credit: 2,930,782 RAC: 1 |
Three train disasters in a month. Lac Megantic in Canada, Bretigny-sur-Orge in France and Santiago de Compostela in Spain. Railways need more safety, there should be more automation to correct human errors. It seems that the Spain railroad stretch did not have a signaling system which is now mandatory in Europe. In Italy, two high speed trains, one State owned and one privately, go from Milano to Rome and Naples, cutting the time and competing with Alitalia. You don't need to arrive an hour before start time to board a train. Tullio |
rob smith Send message Joined: 7 Mar 03 Posts: 22149 Credit: 416,307,556 RAC: 380 |
Three accidents, three different root causes. The one in Canada was the result of poor operating practice, accompanied by poorly defined regulations applying to just about every party involved. In short an accident waiting to happen. The one in France, which is part of Europe was partially blamed on a signalling problem, and partly on "human factors". And this last one looks to be a combination of a poorly conceived speed and signalling strategy, which allowed, or led, the driver into a situation where excessive speed was not prevented. The EU legislation is not as clear as you make out, there are many "escape clauses", mostly to do with the speed and age of the line age. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
Sirius B Send message Joined: 26 Dec 00 Posts: 24870 Credit: 3,081,182 RAC: 7 |
Three train disasters in a month. Lac Megantic in Canada, Bretigny-sur-Orge in France and Santiago de Compostela in Spain. Railways need more safety, there should be more automation to correct human errors. It seems that the Spain railroad stretch did not have a signaling system which is now mandatory in Europe. AND who corrects the automated technology when it fails? Sorry but the Spanish crash is solely down to the driver. It comes down to what is called "Road Training". No driver is allowed to drive on a "road" he is unfamiliar with. He knew the speed restriction so why was it exceeded? Only a fool does that! Unfortunately, that "fool" cost the lives of 78 people, so in my book he should be convicted of murder or at least negligent manslaughter! |
tullio Send message Joined: 9 Apr 04 Posts: 8797 Credit: 2,930,782 RAC: 1 |
Planes use autopilots. Trains could do the same. Tullio |
Sirius B Send message Joined: 26 Dec 00 Posts: 24870 Credit: 3,081,182 RAC: 7 |
Planes use autopilots. Trains could do the same. Now that's plain silly, you should know better. Remember the Turkish Airlines disaster regarding the autopilot? edit: Well at least someone agrees with me...... Driver formally detained The driver, who was injured and is under guard in hospital, is accused of "crimes related to the accident", they say. |
rob smith Send message Joined: 7 Mar 03 Posts: 22149 Credit: 416,307,556 RAC: 380 |
To an extent the latest control and signalling systems contain a form of "autopilot". However if the ground based part of the system makes a mistake, say by sending out the wrong permitted speed to the train then you have the potential for a disaster. As Sirius says there is no substitute for knowing the route that is being driven "like the back of your hand". Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
tullio Send message Joined: 9 Apr 04 Posts: 8797 Credit: 2,930,782 RAC: 1 |
A pilot can disengage an autopilot by pushing a button. On a ship it is more complicated, you have to type a password. This is the reason why the Esso Valdez tanker went aground, as told me by my brother, who is a ship captain with a 40 years experience. All airline flights use autopilots. Tullio |
Donald L. Johnson Send message Joined: 5 Aug 02 Posts: 8240 Credit: 14,654,533 RAC: 20 |
Automated systems, noo matter how well designed and maintained, will suffer component failure and malfunction. And at some point, the cost of additional safety and back-up systems becomes prohibitive. A competent, experienced, and alert driver is the best back-up to automated systems, but even the best driver will have a bad day. We are only human, falible and imperfect, as are everything we design and build. As long as we build and operate high-speed, high-energy systems, there will be mishaps and casualties. Donald Infernal Optimist / Submariner, retired |
W-K 666 Send message Joined: 18 May 99 Posts: 18996 Credit: 40,757,560 RAC: 67 |
But the problem with highly automated systems is that the human backup is usually bored out of their brains and therefore not alert. How many aircraft incidents have been reported in recent years where the pilots have either not reacted, example Minneapolis 2009, or reacted wrongly example Air France also 2009. |
David S Send message Joined: 4 Oct 99 Posts: 18352 Credit: 27,761,924 RAC: 12 |
There are some transit systems that operate completely automatically, with no one at all at the controls. San Francisco's BART subway has someone in the cab just to push a button to close the doors and go, and to hit emergency stop in the event of an obstruction on the track. At minimum, a locomotive has an alerter (which replaced the old dead-man pedal). At irregular intervals, it sounds a tone and the engineer has to do something, usually just touch his console (or change the way he is touching it), within a certain amount of time or it will apply the brakes. Now in development in the US and Canada is a system called Positive Train Control, which will track the position and speed of trains, and even monitor road crossings for cars and people on the tracks, and will initiate first a warning to the crew and then a brake application if the maximum safe speed is violated. (This was mandated by Congress in the wake of the Metrolink crash in Chatsworth a few years ago.) Amtrak's Northeast Corridor and the segments where it operates at speeds faster than 90 mph in Michigan and Illinois already have such systems, although they may not be totally compatible with the national standard being developed. (Amtrak built its system to fit its needs; the standard needs to fit the needs of everyone.) This is being designed as an overlay to whatever dispatching system is in place on any given line. I don't know what the safety systems are like in Europe, but I'd be surprised if they aren't similar. This is why I'm surprised the Spanish train was able to go so fast in that spot. Update: just as I wrote that, a TV news report said there are 2 safety systems that should have regulated its speed. David Sitting on my butt while others boldly go, Waiting for a message from a small furry creature from Alpha Centauri. |
rob smith Send message Joined: 7 Mar 03 Posts: 22149 Credit: 416,307,556 RAC: 380 |
And that boredom is the reason why most modern train control systems have a "positive action" driver vigilance device. A prompt is given and the driver has to make a positive movement to cancel the prompt, failure to respond in time results in the power being cut and the brakes applied. The prompt interval is random, but the response is a "two direction" response - in the UK the driver presses a treadle then releases it. This changed from the old "dead man's handle" after one too many incident where a driver had jammed the handle in the required position. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
Donald L. Johnson Send message Joined: 5 Aug 02 Posts: 8240 Credit: 14,654,533 RAC: 20 |
But the problem with highly automated systems is that the human backup is usually bored out of their brains and therefore not alert. Or Asiana 214 at SFO, where it appears niether pilot recognized that the autopilot was NOT controlling the approach until it was too late, Yee, there is such a thing as too much automation. The driver has to be involved enough to remain alert and aware, not just be a passenger. That's a balancing act between the designers and the operators. Donald Infernal Optimist / Submariner, retired |
rob smith Send message Joined: 7 Mar 03 Posts: 22149 Credit: 416,307,556 RAC: 380 |
To a certain extent its not a contest between the designers and the operators but a contest between the press and the rest of the world. I used to run a risk awareness course, and my opening remark was along the lines "There is a risk that today's session will be interrupted by a London bus coming in through the roof". One young jurno seriously asked what we could do to prevent this unacceptable thing from happening -we were in Preston, on the top floor of a building, so you imagine how remote this event was.... When you've got bozo's like that stirring up the population you get all sorts of stupid systems being imposed, without any thought for the real risk, or the best mitigation for that risk. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
Sirius B Send message Joined: 26 Dec 00 Posts: 24870 Credit: 3,081,182 RAC: 7 |
This changed from the old "dead man's handle" after one too many incident where a driver had jammed the handle in the required position. And because many were "centering" it so that the train just "coasted" at high speed. by "centering" it, it disabled the "deadman's" side of it. I saw that too often I'm afraid & it's all down to the laziness of the driver. However, saying that, I've experienced many deadman's handles where after just an hour of driving my hands hurt badly due to the tension of the spring being set too taunt. So as Donald stated, it's a case of getting the balance between technological & human interface just right. |
Donald L. Johnson Send message Joined: 5 Aug 02 Posts: 8240 Credit: 14,654,533 RAC: 20 |
To a certain extent its not a contest between the designers and the operators but a contest between the press and the rest of the world. Ah, yes..... Ignorant or manipulated journalism leads to public outcry leads to legilative mandates that do more harm than good, but show the voters that their legislators are "doing something" about the problem... [/cynicism] Donald Infernal Optimist / Submariner, retired |
tullio Send message Joined: 9 Apr 04 Posts: 8797 Credit: 2,930,782 RAC: 1 |
At the Honeywell plant in Phoenix which produces avionics both for Airbus and Boeing the engineers of the two departments cannot talk to each other. The philosophy is different. For Airbus the computer flies the plane and the pilot is there just in case. For Boeing the pilot flies the plane and the computer is a help. But at SFO the ILS, not the autopilot, was not working. Tullio |
Sirius B Send message Joined: 26 Dec 00 Posts: 24870 Credit: 3,081,182 RAC: 7 |
But at SFO the ILS, not the autopilot, was not working. Regardless of which did or did not, the technology failed simple as that. |
©2024 University of California
SETI@home and Astropulse are funded by grants from the National Science Foundation, NASA, and donations from SETI@home volunteers. AstroPulse is funded in part by the NSF through grant AST-0307956.