zugmann I'm going to give my wild guess (since everyone else here is...) That the crew tried to recover the air on the first portion without enough handbrakes tied on. PS... this is when you guys should start discussing ECP brakes.
I'm going to give my wild guess (since everyone else here is...)
That the crew tried to recover the air on the first portion without enough handbrakes tied on.
PS... this is when you guys should start discussing ECP brakes.
55 loads with two engines is probably somewhere in the ballpark of 1 HP / ton. You or someone else who runs trains can correct me, but that sounds like it should not be enough to ascend a 2.2% grade, or enough to descend a 2.2% grade using DB alone. But it should be enough to descend a 2.2% grade with working airbrakes. (Speaking of ECP brakes, the CP's test implementation was on trains that had a similar HP / ton and descended a 2.6% grade.)
So why didn't they have air? Your hypothesis makes sense: they tried to go uphill before the air recovered, and they went downhill instead.
Dan
zugmannThat the crew tried to recover the air on the first portion without enough handbrakes tied on.
My reading was that they were trying to push the 55 cars back up the hill, so presumably they had air on that portion of the train. The two locos couldn't move the cars uphill, and, in fact, the train started downhill, overwhelming the locomotives.
One would presume that the engineer dumped the train before he bailed, but we don't know that.
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...
Overmod zugmann PS... this is when you guys should start discussing ECP brakes. You mean like the ones that suddenly released without warning after a couple of hours because their batteries were running low?
zugmann PS... this is when you guys should start discussing ECP brakes.
You mean like the ones that suddenly released without warning after a couple of hours because their batteries were running low?
I was reading something about that incident over in Australia. It said the ECP brakes were dual control mode capable. That after a specified time period, the brakes tansitioned to conventional mode and that allowed the brakes to release.
I would think that in either mode, the fail safe would be to not allow the brake cylinders to release in either mode or whether the batteries in ECP mode became drained. Natural cylinder leakage is another matter.
Jeff
zugmannPS... this is when you guys should start discussing ECP brakes.
It's been fun. But it isn't much fun anymore. Signing off for now.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any
In all fairness, the NTSB doesn't have the manpower to investigate every rail, highway or air accident. Consequently, they have to select which accidents merit an investigation.
In the Trains Newswire article that reported the re-opening of the line, it had this:
The National Transportation Safety Board is not involved in the investigation.
Why is that? Just because there were no injuries or fatalities or hazmat involved? Seems like they might want to investigate how it came to be that an unmanned runaway train ended up going down a hill at a reported 118 MPH. Not sure I trust UP be entirely transparent about it on their own.
How were the air brakes and hand brakes handled preparing to back up the train? The 2 locos in front could not push front cars back up hill. RED FLAG. That means locos in front could not hold train once bake line recharged. Did train start rolling forward when backing up failed? Another try? Time to either take front down hill or send helper to push front back up ?
Is it true that BNSF requires more HP / ton on its grade than UP uses here?
SD60MAC9500 ns145 JayBee A lot of missing information here on the Trains Forum. The train was 154 cars long with 5 locomotives set up 2x1x2. The train crested the top of Cima Hill after climbing the 1% grade. That was the easy if slow part. From the there it it is 17 miles of 2.2% grade with minimal curvature to Kelso, CA. There the grade eases to 1 % down to Cruzero. The train broke a knuckle with the train draped over the top of the hill. After this things are still a bit unclear. It is reported but not confirmed yet that the crew replaced the knuckle and tried to push the front 55 cars back to a joint but the two leading locomotives couldn't move the 7000+ tons back up the grade and instead started down the hill. The Engineer fortunately immediately bailed off the locomotive. A defect detector located part way down the hill reported the train speed as 118 miles per hour. The UP runs this train with just 5 AC locomotives down the 2.2% grade of Cima Hill, but when it gets to Yermo 4 more locomotives get added for the 2.2% grade of Cajon Pass, not because UP thinks they need that many but because BNSF rules require nine locomotives for that heavy a train considering the TPOB and Dynamic Brake axle rating. This was an accident just waiting to happen. Now this sounds like a PSR-caused accident. Close to 19,000 tons down a 17 mile 2.2% grade is insane even if everything is working properly. Little or no margin for error for the train crew to work with. Glad that everyone walked away from this accident alive. Trains have ran away before "PSR".. Highly doubt there's a correlation here.. On the other hand maybe safety is not satisfactory these days.
ns145 JayBee A lot of missing information here on the Trains Forum. The train was 154 cars long with 5 locomotives set up 2x1x2. The train crested the top of Cima Hill after climbing the 1% grade. That was the easy if slow part. From the there it it is 17 miles of 2.2% grade with minimal curvature to Kelso, CA. There the grade eases to 1 % down to Cruzero. The train broke a knuckle with the train draped over the top of the hill. After this things are still a bit unclear. It is reported but not confirmed yet that the crew replaced the knuckle and tried to push the front 55 cars back to a joint but the two leading locomotives couldn't move the 7000+ tons back up the grade and instead started down the hill. The Engineer fortunately immediately bailed off the locomotive. A defect detector located part way down the hill reported the train speed as 118 miles per hour. The UP runs this train with just 5 AC locomotives down the 2.2% grade of Cima Hill, but when it gets to Yermo 4 more locomotives get added for the 2.2% grade of Cajon Pass, not because UP thinks they need that many but because BNSF rules require nine locomotives for that heavy a train considering the TPOB and Dynamic Brake axle rating. This was an accident just waiting to happen. Now this sounds like a PSR-caused accident. Close to 19,000 tons down a 17 mile 2.2% grade is insane even if everything is working properly. Little or no margin for error for the train crew to work with. Glad that everyone walked away from this accident alive.
JayBee A lot of missing information here on the Trains Forum. The train was 154 cars long with 5 locomotives set up 2x1x2. The train crested the top of Cima Hill after climbing the 1% grade. That was the easy if slow part. From the there it it is 17 miles of 2.2% grade with minimal curvature to Kelso, CA. There the grade eases to 1 % down to Cruzero. The train broke a knuckle with the train draped over the top of the hill. After this things are still a bit unclear. It is reported but not confirmed yet that the crew replaced the knuckle and tried to push the front 55 cars back to a joint but the two leading locomotives couldn't move the 7000+ tons back up the grade and instead started down the hill. The Engineer fortunately immediately bailed off the locomotive. A defect detector located part way down the hill reported the train speed as 118 miles per hour. The UP runs this train with just 5 AC locomotives down the 2.2% grade of Cima Hill, but when it gets to Yermo 4 more locomotives get added for the 2.2% grade of Cajon Pass, not because UP thinks they need that many but because BNSF rules require nine locomotives for that heavy a train considering the TPOB and Dynamic Brake axle rating. This was an accident just waiting to happen.
A lot of missing information here on the Trains Forum. The train was 154 cars long with 5 locomotives set up 2x1x2. The train crested the top of Cima Hill after climbing the 1% grade. That was the easy if slow part. From the there it it is 17 miles of 2.2% grade with minimal curvature to Kelso, CA. There the grade eases to 1 % down to Cruzero. The train broke a knuckle with the train draped over the top of the hill. After this things are still a bit unclear. It is reported but not confirmed yet that the crew replaced the knuckle and tried to push the front 55 cars back to a joint but the two leading locomotives couldn't move the 7000+ tons back up the grade and instead started down the hill. The Engineer fortunately immediately bailed off the locomotive. A defect detector located part way down the hill reported the train speed as 118 miles per hour.
The UP runs this train with just 5 AC locomotives down the 2.2% grade of Cima Hill, but when it gets to Yermo 4 more locomotives get added for the 2.2% grade of Cajon Pass, not because UP thinks they need that many but because BNSF rules require nine locomotives for that heavy a train considering the TPOB and Dynamic Brake axle rating. This was an accident just waiting to happen.
Now this sounds like a PSR-caused accident. Close to 19,000 tons down a 17 mile 2.2% grade is insane even if everything is working properly. Little or no margin for error for the train crew to work with. Glad that everyone walked away from this accident alive.
Trains have ran away before "PSR".. Highly doubt there's a correlation here.. On the other hand maybe safety is not satisfactory these days.
Yeah right, cause back in the olden days every railroad ran 20,000 ton trains down 2.2% grades. PSR wouldn't have affected that at all...
My personal speculation is that the hoppers were grossly overloaded, perhaps by people not recognizing how little would constitute a 'full load' per car. Knuckle failure over a summit in a train with midtrain DPU indicates to me a considerable node shift in the first section of the consist -- perhaps indicating excessive acceleration of the head end of the train even with part of it still on the vertical curve going over the summit. That two AC units not only couldn't back 55 cars over the summit, but couldn't hold the train from a stop with full AC dynamics and what I assume was a full emergency set backed up with handbrake application is... suspicious to me.
Of course I immediately add "we should wait for the report" and that I defer to anyone with operating experience.
tree68I got the impression (corrections welcome) that the mid-train DPU was with the ~100 cars behind the break. This because of the statement that the two lead locomotives were unable to push the 55 cars back up the hill to make the hitch. If the DPU was in the forward portion of the consist, it would have made three locomotives trying to push the 55 cars up the hill to make the hitch. The question would be what state the engineer left the train in when he bailed. Was he able to make a full service? Did he place the two lead locos in dynamics? Or did he get while the getting was good?
The question would be what state the engineer left the train in when he bailed. Was he able to make a full service? Did he place the two lead locos in dynamics? Or did he get while the getting was good?
Irrespective of which side of the broken knuckle the DPU was located. If the head end segment of the train was unable to be controlled to less than 15 MPH then the available braking power - both dynamic and air were insufficient to keep the train from running away down the grade.
I suspect that a the time the Engineer bailed, the locomotives were in 8th notch dynamic braking and after a full service application didn't control the train and emergency application was made and still the train gained speed - then he bailed.
Presuming that the lead engine was Alerter equipped, at some time after the Engineer departed - the Alerter would have 'done its thing' without stopping the train.
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I got the impression (corrections welcome) that the mid-train DPU was with the ~100 cars behind the break. This because of the statement that the two lead locomotives were unable to push the 55 cars back up the hill to make the hitch. If the DPU was in the forward portion of the consist, it would have made three locomotives trying to push the 55 cars up the hill to make the hitch.
No air doing 118 at a defect detector saw something on Facebook saying the engine pinged GPS at 149 before slowing down. Sure these monsters are safe to run through the mountains. Union Pacific better be glad the only hazmat spilled was diesel fuel in that area. I shuddered what the environmental damage could have been with an oil train or chemical train derailment in that area.
Personally, I think this incident highlights that DPU's need to be placed for their braking power as much as for the pulling power.
Sounds as if the head 2 plus the 1 in the middle weren't able to develop the Dynamic Braking power necessary to keep the 'reamaining' train to the control level required so that the air brakes could maintain a safe speed down the grade.
Once the train exceeds the ability of the air brakes + dynamic braking to control the train - the only option is to JUMP right then and there, (NTSB testing has shown that AB can't control a tonnage train down a 2% grade at a speed higher than 15 MPH) because the train will not be going any slower from that point until the point of derailment.
Since CSX was not into DPU operation in my area of responsibility at the time of my retirement - I don't know what concepts are being utilized for the placement of DPU's regarding either trailing tonnage under power or excessive buff loadings under dynamic braking. Both forces need to be considered in the placement of DPU's in trains.
The line is open again.
https://www.trains.com/trn/news-reviews/news-wire/union-pacific-reopens-cima-subdivision-after-derailment-of-runaway-iron-ore-train/?fbclid=IwAR1MyhZobb46ao-XVADF-fTSlqPLdubbs5e4x9iMrN8cCNO15Cnv8r6pGbE
JayBeeA lot of missing information here on the Trains Forum.
Thank you for your thorough summary. It explains the partial info I had seen elsewhere.
JayBeeThis was an accident just waiting to happen.
Indeed!
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I was a little off on the distance, it is 18 miles WSW of Cedar City, UT.
Tree68 has it pegged correctly with the Columbia.
timz A new mine? Don't see anything that close to Cedar City on the aerials.
A new mine? Don't see anything that close to Cedar City on the aerials.
Both located near Iron Mountain, in Iron County, UT
Homestake (uranium and vanadium)
37.61619 -113.38813
Columbia (iron ore)
37.61702 -113.38938
The mine is about 2 miles SW of Cedar City, UT, on a branch off the former LA&SL. A shortline brings the loaded cars down to the UP mainline at Lund, UT
One possibility
https://goo.gl/maps/gQbS7rw5rCXrvEpX6
No doubt came from Utah somewhere.
Where was the ore coming from and where was it going? The only mine that I could think of in that area is the old Kaiser Steel Eagle Mountain one, but that's been closed for years, IIRC.
Quite the photo:
https://www.vvdailypress.com/story/news/2023/03/28/train-derails-in-mojave-national-preserve-east-of-barstow/70054506007/
Iron ore is just a tad "dirtier" than iron pellets (taconite).
Besides, "charred" makes better headlines...
OvermodBe sure to watch the video. There is no evidence of heavy brake application on the locomotive -- I'd have expected at least blued wheels as in some of the other grade-related accidents. Strange that iron ore would be moving in aluminum hoppers. NOT saying that any 'fire' would be associated with that combination. Will be interesting to find out where the crew left the cab. Judging by the state of the tank on the lead locomotive, much of the 'fire' might have been diesel fuel assisted -- and the 'small leak' left for hazmat crews to clean up might represent whatever residual fuel remained in the broken tank.
Strange that iron ore would be moving in aluminum hoppers.
Will be interesting to find out where the crew left the cab.
Judging by the state of the tank on the lead locomotive, much of the 'fire' might have been diesel fuel assisted -- and the 'small leak' left for hazmat crews to clean up might represent whatever residual fuel remained in the broken tank.
Why strange - lighter weight of car allow more weight for the contents. Freight rates are based on net product weight.
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