It would be 3 joints. 2 at the joints separating the 3 rails and then 1/2 of the joint on each end, since it would be shared with the adjoining rails. All this talk of joints makes me think of the Amtrak Tucson thread...
BaltACD charlie hebdo Two joints. Initial Joint - 39 feet of rail - 2nd Joint - 39 feet of rail 3rd Joint + 22 feet to get to 100 feet.
charlie hebdo Two joints.
Initial Joint - 39 feet of rail - 2nd Joint - 39 feet of rail 3rd Joint + 22 feet to get to 100 feet.
But only two joints within the 100 foot span unless you count a joint to the rail preceding.
A potentially important point that seems not to be quite realized yet is that jointed rail does not accommodate expansion or contraction unless the joints are sequentially loosened and retightened while the temperature is low or high. In the old days of roving section gangs this could be done regularly with the weather. When I first read about 'sun kink' the account (I think it was on the Burlington in Kansas) said that when the bolts were loosened the rail ends came together with a crack like a pistol shot, an indication of the strain built up in those rails... but also an indication the stress wouldn't 'relieve itself' at the joints without explicit action.
charlie hebdoTwo joints.
Never too old to have a happy childhood!
Two joints.
cx500 BaltACD Welded Rail is a technology that still has not been MASTERED. Sun kinks can also occur on jointed rail, especially branch lines that see minimal maintenance. During the hot days of summer several lines are operated only at night or early morning. Experience is a great teacher.....
BaltACD Welded Rail is a technology that still has not been MASTERED.
Welded Rail is a technology that still has not been MASTERED.
Euclid “Sun kinks have already caused more than 2,100 train derailments in the U.S. over the past 40 years, or about 50 derailments a year, on average.”
“Sun kinks have already caused more than 2,100 train derailments in the U.S. over the past 40 years, or about 50 derailments a year, on average.”
tree68If you are going to sue, you go for the deep pockets.
True.
Still in training.
SUN KINK HYPOTHESIS:
So as I understand it, the train was westbound, and passed through Joplin on straight track. About 3000 feet west of Joplin, the train entered a short curve about 15 degrees to the right. In that curve, it started derailing behind the engine. About 1000 feet further, the engine passed over the east facing point switch of the passing siding, and stopped approx. 100-300 feet beyond the switch. So the entire range of derailment was about 1000 feet long.
Before the train reached the short curve to the right, there was a latent sun kink existing there in the form of excess rail linear compression due to heat expansion and possibly to localized compressive stress in the rails that was caused by a previous train.
Investigators have video taken from the camera on the engine which will show what the engineer saw when approaching and passing over this 1000 ft. stretch. According to the news reporting, I assume that the engineer saw nothing unusual with the track such as a manifested sun kink.
However, somewhere behind the engine, as the track was being vibrated and worked by the passing train, the latent sun kink consequently began to manifest by buckling track rail and ties.
Before the train actually derailed, the track and ties would have exhibited the development of misalignment that would soon be noticeable as a bumpy ride to people on board the cars. Quickly, the misalignment increased to the point where the cars began a tendency to leap across the misalignment loops rather than to negotiate them. For the most part, these jumps over the kinks derailed the car trucks and they failed to re-rail again after starting their jump. With several more cars following this course of action at approx. 70 mph, they were on the ground at this relatively high speed. They would all likely have been tearing up the track by breaking and bending rails and plowing up ties.
The actual sun kink manifested may have only been one or two bows, or it may have been several in the common serpentine pattern. Initially the first cars to derail might have tended to stay in line and remain coupled at such a high speed. In any case, as the track was progressively damaged by the derailment, the derailed cars lost ability to act as a train at speed and were thus subjected to increasing departure from track alignment, impacts, and damage.
In investigating the site of this scenario, one would look for the first sign of wheels on the ground as indicated by creases/splintering on tops of ties, abrasion marks on rail, etc. to indicate the initial point of derailment.
Once that point of initial derailment is found, any other type of track misalignment preceding that point would be evidence of a sun kink. Both a derailment and a sun kink can cause bowed rails. But any violent abrasion and tearing of the track would not have been caused by a sun kink.
Once the derailment began, there might have been considerable evidence of sun kink damage that developed beyond that point as the train proceded in its course of derailment, but much if not all of that range of sun kink damage may have been obliterated by the subsequent derailment damage. So the key to proving a sun kink as the cause would be to find the point of derailment and then find track misalignment before that point of derailment. That would show track misalignment that could not have been caused by the derailment, and thus could have been caused by a sun kink.
So the sun kink causes the track to buckle and bow out rather gracefully, but it can move track enough to disrupt it to point being able to easily derail a train. Then the derailment of the train violently tears up the track structure.
From this link:
https://www.climatecentral.org/news/climate-change-warp-railroad-tracks-sun-kinks-17470
BaltACD diningcar Just learned that several injured passengers have filed a lawsuit against Amtrak and BNSF. The attorney representing them claims BNSF had issued a SLOW ORDER for the east Buelow switch location. Guess we will have to see if that is true because #7 was reported to be going approx. 75 Mph which would certainly be more than a slow order permits. A Slow Order or a Heat Order that calls for reduced speeds? I don't know BNSF rules. On CSX Heat Orders, when issued, are effective from 1300 to 1900; outside those hours normal speeds apply. Genuine Slow Order applies as long as the order is in effect.
diningcar Just learned that several injured passengers have filed a lawsuit against Amtrak and BNSF. The attorney representing them claims BNSF had issued a SLOW ORDER for the east Buelow switch location. Guess we will have to see if that is true because #7 was reported to be going approx. 75 Mph which would certainly be more than a slow order permits.
Guess we will have to see if that is true because #7 was reported to be going approx. 75 Mph which would certainly be more than a slow order permits.
A Slow Order or a Heat Order that calls for reduced speeds?
I don't know BNSF rules. On CSX Heat Orders, when issued, are effective from 1300 to 1900; outside those hours normal speeds apply.
Genuine Slow Order applies as long as the order is in effect.
Among other things, this article has one of the lawyers claiming that the slow order was due to ongoing track maintenance:
https://abcnews.go.com/US/injured-passengers-file-lawsuits-amtrak-montana-train-derailment/story?id=80418153
They don't say what speed the slow order required.
If a slow order was in effect I'm surprised the NTSB did not mention it at their initial press conference.
Greetings from Alberta
-an Articulate Malcontent
Lithonia OperatorOh Lord. Not another engineer-error case. If BNSF clearly and definitively communicated the slow order, then I don't see where they are at fault.
If you are going to sue, you go for the deep pockets.
It could probably be argued that regardless of communication that may have occurred, the engineer was acting on behalf of BNSF.
Further, one would think that PTC, assuming it was working, should have enforced the slow order. That should be interesting.
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
Aren't slow orders one of the things enforced by PTC?
BaltACDOn CSX Heat Orders, when issued, are effective from 1300 to 1900; outside those hours normal speeds apply.
It shouldn't be difficult to find BNSF policy on heat orders.
diningcarJust learned that several injured passengers have filed a lawsuit against Amtrak and BNSF. The attorney representing them claims BNSF had issued a SLOW ORDER for the east Buelow switch location. Guess we will have to see if that is true because #7 was reported to be going approx. 75 Mph which would certainly be more than a slow order permits.
Oh Lord. Not another engineer-error case. If BNSF clearly and definitively communicated the slow order, then I don't see where they are at fault.
Just learned that several injured passengers have filed a lawsuit against Amtrak and BNSF. The attorney representing them claims BNSF had issued a SLOW ORDER for the east Buelow switch location.
I just think we have to wait until the preliminary report comes out within a few weeks. Then we'll have more to chew on.
I am reminded of the expression about "If a tree falls in the forest and no one hears it, does it make a noise. Amtrak derails in a sparsly populated area with no news peope around and while there was a couple of days of speculation, it has become very quiet here. How can we learn what the Engineer (assuming he has been interviewed) has said. Has anyone seen the locomotives forward facing camera video? Awfully quiet hear.
charlie hebdo Thank you for the correction and the summaries of expert opinions.
Thank you for the correction and the summaries of expert opinions.
My comments about misattribution:
Many news articles describe an investigation by the NTSB. Then they quote experts by name, professional title, and employer. Mixed in are similar statements actually by the NTSB. Some of these experts make statements about what investigators will look for, and then go on to make the same kind of speculative statements that any member of an investigation would make.
So my perception was that these quoted experts are actually contributing to the investigation on behalf of the NTSB. Granted, that was not made explicit, but it was not ruled out either. But it was my mistake to attribute the statements by experts to the NTSB without having proof.
So that is my explanation and I have edited the post (on the previous page) where I directly attributed the professional speculation to the NTSB.
I include that professional speculation here with the identification of the people who actually stated it. I have no idea how or if they have any relationship to the NTSB or will contribute to this NTSB investigation.
COMMENTS IN NEWS COVERAGE OF THE WRECK:
(all of this is in many news articles to varying extents)
Railroad safety expert David Clarke, director of the Center for Transportation Research at the University of Tennessee, said accident scene photos show the derailment occurred at or near a switch, which is where the railway goes from a single track to a double track.
Clarke said the two locomotives and two cars at the front of the train reached the split and continued on the main track, but the remaining eight cars derailed. He said it was unclear if some of the last cars moved onto the second track.
“Did the switch play some role? It might have been that the front of the train hit the switch and it started fish-tailing and that flipped the back part of the train,” Clarke said.
Another possibility was a defect in the rail, Clarke said, noting that regular testing doesn’t always catch such problems.
Allan Zarembski, director of the University of Delaware’s Railway Engineering and Safety Program, said he didn’t want to speculate but suspected the derailment stemmed from an issue with the train track, equipment, or both.
Railways have “virtually eliminated” major derailments by human error after the implementation of positive train control nationwide, Zarembski said. He said NTSB findings could take months.
Bob Chipkevich, who oversaw railroad crash investigations for several years at the NTSB, said the agency won’t rule out human error or any other potential causes for now.
“There are still human performance issues examined by NTSB to be sure that people doing the work are qualified and rested and doing it properly,” Chipkevich said.
Chipkevich said track conditions have historically been a significant cause of train accidents and noted most of the track Amtrak uses is owned by freight railroads and must depend on those companies for safety maintenance.
******
Investigators will look at “everything,” including the switch, wheels, axles and suspension systems, as well as the track geometry and condition, including any cracks, said Steven Ditmeyer, a rail consultant and former senior official at the Federal Railroad Administration. He said a switch like the one in Joplin would be controlled by the BNSF control center in Fort Worth, Texas.
Sometimes rail lines can become deformed by heat, creating buckles in the tracks known as sun kinks, Ditmeyer said. That was the cause of a derailment in northern Montana in August 1988, when an Empire Builder train veered off the tracks about 170 miles east in Saco, Montana.
The NTSB concluded that an inspection failed to catch a problem in the track, and officials did not warn trains to slow down on that stretch. The crew saw the track had shifted, but the train was going full speed and could not stop before derailing.
Temperatures were in the high 80s Saturday near Joplin, according to the National Weather Service.
Russ Quimby, a former rail-accident investigator for the NTSB, said heat is the most likely explanation. He is convinced because the locomotives in front did not derail, but eight lighter coach cars behind them did.
“This has all the earmarks of a track buckle also,” Quimby said. “Sometimes a locomotive, which is heavier, will make it through” a buckled track, “but the cars following won’t. You saw that in this accident,” he said.
Quimby said a malfunction of the switch seems less likely because, he believes, the switch would have been inspected when the track in the area was checked last week.
charlie hebdo OM: I largely agree, but Euclid should have been honest enough to admit he misattributed a comment to the NTSB. The former NTSB staffer's comment carries weight, but not nearly as much as that of an actual investigator.
OM: I largely agree, but Euclid should have been honest enough to admit he misattributed a comment to the NTSB. The former NTSB staffer's comment carries weight, but not nearly as much as that of an actual investigator.
Yesterday, I said this: "The information I cited was not on behalf of the NTSB, but rather by apparently qualified experts commenting on the investigation seeking the cause of the wreck."
Of course it was a mistake.
Argument - Monty Python - YouTube
Now that everybody is bickering at each other... or worse... and we've jumped backward and forward between quite possibly unrelated wrecks without discrimination, can we stop this?
Euclid made some bonehead academic mistakes, but the point remains that someone qualified enough to have BEEN on the NTSB, and who therefore fully understood 'how the NTSB works', made a statement to the media in which he stated he thought sun kink was an explanation for the recent wreck. Claiming that this is somehow a bogus opinion because current NTSB staffers aren't saying so 'for attribution at this time' is sophistry.
If there is any point whatsoever in continuing with this sun-kink supposition let it revolve around the ex-NTSB guy's credentials, with the actual track guys around here chiming in on the actual practice that would support or question what he said and how likely it might apply here.
At this point I suspect there is very little we'll hear about this until the NTSB actually reports something... and that may be a relatively long time. If someone wants a thread on sun kink, or stability and accident safety of high-level cars, or how to extract shaming confessions out of recalcitrant erring posters, it would be better to start a new topic with appropriately monitory title and leave this thread until more is actually known and established.
Goodtiming “Never argue with a fool; onlookers may not be able to tell the difference.” – Mark Twain.
“Never argue with a fool; onlookers may not be able to tell the difference.” – Mark Twain.
They also tend to drag you down to their level and then beat you with experience.
Some people sure are full of themselves, among other things.
Backshop I don't argue with people who can spot a low spot in a rail by holding a ruler up to their computer screen.
I don't argue with people who can spot a low spot in a rail by holding a ruler up to their computer screen.
Interesting. I've found that being able to do that trick doesn't go very far with most people.
PS--People give "opinions" all the time. There's no law against it. This isn't a court with sworn testimony and expert credentials.
Yes. But when you present something as fact that is not, don't expect not to get called on it. Even if it's a hobby.
Ed
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