theodorefisk Definitely not a stringline derailment. There are pictures of stringline derailments on the Santa Fe involving either empty autoracks or empty TTX 89' TOFC flats. All the cars laid over on the inside of a curve. Ted
Definitely not a stringline derailment. There are pictures of stringline derailments on the Santa Fe involving either empty autoracks or empty TTX 89' TOFC flats. All the cars laid over on the inside of a curve.
Ted
Ted,
As far as I can see from the photo, all the cars DID lay over on the inside of the curves. I may be missing something, though. Could you please explain where I'm wrong?
Ed
I find it interesting that, besides the car tipping, there was extensive track damage.
I suppose that the centripetal force on the cars was transmitted through the wheel flanges. And the track could slide because there's really not much holding it laterally besides a "buncha gravel". That and the compressibility of steel rail.
7j43k I believe this is the FRA finding on this accident: BNSF TRAIN WITH 5 LOCOMOTIVES 61 CARS & 3 HELPERS. HELPERS WERE BEHIND 16TH CAR IN VIOLATION OF BNSF SUPT. NOTICE #96. THE HEAD END PULLED THRU HELPERS CAUSING THE 1ST CAR BEHIND HELPERS MIDDLE BAY EMPTY SPINE CAR TO DERAIL. I would love to read the whole document, but I couldn't come up with it. Ed
I believe this is the FRA finding on this accident:
BNSF TRAIN WITH 5 LOCOMOTIVES 61 CARS & 3 HELPERS. HELPERS WERE BEHIND 16TH CAR IN VIOLATION OF BNSF SUPT. NOTICE #96. THE HEAD END PULLED THRU HELPERS CAUSING THE 1ST CAR BEHIND HELPERS MIDDLE BAY EMPTY SPINE CAR TO DERAIL.
I would love to read the whole document, but I couldn't come up with it.
Ed,In short engineer error. I would also like to read the whole report since it includes tonnage,weather conditions time of day,type of locomotives and train speed.
I knew there was more involved then just common stringling.
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
Southern Pacific, San Antonio Division, Employees Timetable No. 16, Effective Sunday October 28, 1984, Special Instructions for All Subdivisions, Item 5, entitled "Placement of Restricted Cars in Train With or Without Helper", paragraph B states: When tonnage of any train excluding engines exceed 4000 tons, the weight of each of the first five cars behind engine must weigh 50 tons or more. This restriction will not apply (1) When there are less than 20 loaded cars in the train (2) When there are not 5 loaded cars in train weighing 50 tons or more.
Interesting discussion guys, I admit I was very curious about this incident, which is why I posted this. At first it looks like the problem was obvious, then I started to notice others things that didn't make sense.
I did assume that this was the head engine at first, that seemed odd, it beimg a mid train Helper makes much more sense, assuming the coupler broke when the engine tumbled.
A pusher "big holing" or mishandling of the train sounds logical as well, I wish I knew how to look up the FRA investigation to find the cause for this.
Thank you for your observation.
"The true sign of intelligence is not knowledge but imagination."-Albert Einstein
http://gearedsteam.blogspot.com/
BRAKIE Also note the loaded bulkheads derailed to the opposite side..
Also note the loaded bulkheads derailed to the opposite side..
That would happen with stringlining--the cars fall to the inside of the curve,which is what happened.
But I think if it was only stringlining, the track wouldn't have been damaged. At least, not to that extent.
I speculated that a big-hole on potential trailing pushers could be the cause. I also note that there's some replacement rail in place on the side of the track. I also wonder if someone did an oops while prepping for the rail change.
I think that that location likely had a pretty tight curve. Another wreck is shown here at the same location:
From looking at other pictures, there appear to have been other owies at this location. Over to the right, it looks like they've started a cut to go around the tunnel. Which they did.
7j43kAlso note that the inside rail in the area of the turned loco has rolled. I kinda have a problem with so much track movement from just a simple stringline. I wonder if there was a trailing pusher that big holed. And the sudden tension on the train produced BOTH a stringline and a track migration.
Ed,I think there's more to that derailment then simple stringlining.I agree with your observation.Also note the loaded bulkheads derailed to the opposite side.. Something went terribly wrong and we see the results.
I've seen empty flats,bulkheads,gons and boxcars behind the engines with no issues.
Here's another shot of the wreck:
Here's a pull-back from the above shot. It shows, up near the end of the spine-car set, that both rails of the track slid downhill:
http://www.railpictures.net/viewphoto.php?id=115681&nseq=12
Also note that the inside rail in the area of the turned loco has rolled. I kinda have a problem with so much track movement from just a simple stringline. I wonder if there was a trailing pusher that big holed. And the sudden tension on the train produced BOTH a stringline and a track migration.
And I can see that I was wrong about the flats. Yup, a five-unit spine.
Curious.
I suspect stringlining started it, but that doesn't really account for the loco going over. I suspect that happened because when the spine cars came unglued, something snagged into the ties and it was THAT which led to the loco overturning. Look at the spot in the track a car length or two back from the overturned loco. You can see a truck sitting there next to the very short section of distorted, torn up track
Mike Lehman
Urbana, IL
Looks like stringlining to me. All the cars tipped to the inside of the curves.
WHY there was stringlining is kind of open. I do see what looks like 5 empty flat "cars" behind the tipped loco--a flat with a steel truss on it, a three-unit spine, and a container flat. Those are blatantly empty. It's kind of a surprise that that loco would have tipped, too. And it looks like, when it tipped, it took out the track underneath it. As opposed to all the cars, which didn't. It is, though, by far heavier.
The caption says the locos in view were helpers that had emerged from the tunnel. That would imply they were mid-train. I suppose there could have also been a helper on the end. If so, perhaps it contributed to the problem. Or perhaps there was just a lot of loads "back there".
(I was composing this as Dave posted his comments, so there's a bit of redundancy. I'll leave it)
I would argue that "stringlining" was the cause since all the cars were derailed to the inside of the curves, the cars in the right hand curve were derailed to the right and the cars in the left had curve were derailed to the left.
The real cause was the empty spine car right behind the engines, which is against the rules on modern roads.
The train came out of the tunnel and the spine cars derailed to the inside of that curve and then as the helper set (mid train) went around the left hand curve they pulled the spine cars to the inside of the left hand curve, pulling the rear of the trailing helper towards the dump until it rolled over. You can see how the rail is pulled to the inside of the curve near the derailed helper engine.
Since the cars first derailed to the inside of the right hand curve out of the tunnel the rest of the cars behind the spine cars hit that damaged track and derailed to the inside of that curve.
Dave H. Painted side goes up. My website : wnbranch.com
Yup, no stringlining there. If you watch carefully, you can see the prototype often has unloaded cars in front of loaded ones - it's easy to tell with an open car like a flat or centerbeam flat, gons can be touch because they could be loaded with steel plates which won't show over the side, and closed cars you have to look at the springs. It doesn't work too good on our models because physics doesn't scale and model draft gears isn't really set up to direct most of the force through the center sill. And also train handling. Without the heavy weight for momentum, our models respond much too quickly to throttle commands.
You CAN run models with lighter weight ahead of heavier cars, and do it successfully, you just have to have a light touch on the throttle. All of my cars that are in service have NMRA recommended weights, but I have some open hoppers that, with a load installed, are well over weight (hydrocal cast bases for the loads). I can put those hoppers near the tail end of the train and not have a problem - though this is on fairly generous 28" radius curves. That's another factor - even a fairly wide HO model curve of 30" is pretty tight realtive to the prototype. So there's another factor that makes models much more likely to stringline than the real thing.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
I don't think that was a case of stringlining as much as it was a operation error..There was pushers on the rear and if the lead engineer applied some air then that could happen. Of course a rail could have turn as well.
Note how the cars are derailed to the left and right. A stringline derailment all cars derail on the same side.
Its interesting how physics in the 1:1 world equate to our model world. A perfect example here.
Notice how the light cars directly behing the motive power "stringlined" between the motive power and the heavier cars, or was it the boxcars that derailed first and pulled the motive power over?
On my railroad I have some fairly heavy grades, I must build the train carefully (ore cars first, empty log cars last) otherwise I will experience the same dilemma. Careful train handling also applies!