For as unfortunate and costly as the flattened drivers on U.P locomotive #844 are, it seems like just a minor footnote compared to the uncontrollable runaway that caused the flat wheels. That runaway is a huge deal. It is too early to learn if operator error played a part. If it was a function failure of the M.U. system, I would have thought there would be some type of failsafe shutdown that the crew could have used to stop the diesel helper. If it is a design flaw in the M.U. system, that will raise lots of questions.
It would be interesting to hear form those who can explain how the helper is controlled in conjunction with the operation of the steam locomotive. Perhaps this has been thoroughly explained in technical articles, but I am not aware of such.
It is an interesting line to follow. This is the first time that anybody seems to have put forward the ‘unstoppable runaway’ theory as to what happened to 844, and why the drivers were flattened. Kinda makes sense, after a fashion though.
Like many others I’ve had the privilege of ‘chasing’ 844 on several occasions, and the east of her operations always has seemed flawless, and smooth. In countless videos there have been any number of different diesels included for ‘protection’ of the train. It was sort of a given that there was a control stand to control the diesels from the cab of 844(?).
If it was in fact a ‘runaway’ diesel that caused the flat-spotting incident, would not a brake application not only effected the locomotives, but the consist as well? There seems to be not published information as to the engineer’s identity, but having watched Steve Lee and the crewmen who worked for him, and around him, these seemed to be consummate professionals. I would suspect that the engineers would have been well trained under Steve’s tutialedge , and capable of handling those situations…
I would bet more on the aspect of a mechanical problem of some sort, rather than human error. One thing for certain, The UP guys will know soon the whats and whys of what caused 844 to have failed on the trip. [2c]
That theory is all over the place. It is not just something I thought up. In fact it is being offered as the flat-out explanation of what went wrong. However, as far as I know, the U.P. has not officially confirmed it.
What is being offered as pure theory and conjecture (and where there is much disagreement) is how the diesel became unstoppable, what braking and shutdown options existed, why they did not work at first, what finally did stop the train, why somebody could not have gotten to the diesel and shut it down, and how the steamer’s wheels got flattened in the ordeal.
I am not buying the runaway locomotive theory at all. I was a former locomotive mechanic and I have never heard of a locomotive reeving up for no reason and going out of control.
There is many ways to stop a locomotive and all are applicable to the 844 situation.
1.) Hitting the emergency stop button in the cab which shuts the locomotive down.
2.) Turning off the generator field switch(located in the cab) which would turn off power to the traction motors.
3.) Putting the throttle in idle or stop position.
4.) Moving the forward/reverse lever to neutral.
5.) Start using dynamic brakes.
6.) Move the brake handle to the Emergency position which automatically brings the locomotive back to idle despite throttle position. This would apply if the 844 thrown brake handle into emergency also.
7.) Moving the main knife switch in the cab to OFF which shuts off all electrical functions.
8.) Pushing the emergency fuel cut off button near the fuel tank filler neck (this can be done by laying down on the walkways).
9.) Pushing the fuel cut off switch in the engine compartment.
Shutting off the fuel pump circuit breaker or generator circuit breaker from the cab.
All of these options could have been done in less than ten seconds. Some of these options would make no difference if the locomotive was being controlled by remote control. Even in that case all someone had to do was to turn off the generator switch or hit the emergency stop button. It’s sounding more like operational error then mechanical problems.
Well, if it was an operator error, it might not be accurate to say the locomotive ran away. But either way, the locomotive was defying the intent of the operator. As I understand it, there was nobody onboard the locomotive, and apparently they could not get to it. I wonder why they could not have gotten to it from either the head end or from behind it.
You mention several ways to shut down the power from the locomotive. Some would require being in the cab, and some could be done through the remote controller. I wonder how unique or specialized that control system is. The more unique it is, the more it seems likely that there could have been an unanticipated problem with how the controller was designed and/or how it worked with that particular diesel locomotive. This issue of what could have been done or should have been doable seems to be the most disputed aspect of the incident.
All of which require someone aboard the Dismal to perform, which it has been stated that there was no one aboard to do any of them. The Diseasal was running as a helper using a remote control stand in the cab of the 844, so if it lost the communication link to the hel
Quite a bit of conjecture floating around, but at this point IF the problem was a runaway helper diesel, (and WHY would 844 need a helper anyway?) then the solution from now on is to put a “warm body” in the diesel cab as a human “fail-safe”.
Sabotage? Ahhhh, I don’t know, seems like a bit of wild talk at this point. Who, why, and “what for” would be my questions.
Here is a very interesting piece of discussion about MU controllers used between steam and diesel locomotives. The first four posts are quite interesting. I wonder if the U.P. controller is a custom built unit, or if it is the latest remote control technology signed off on by all of the regulatory authorities.
To what extent could the current remote control yard engine technology be applied to this application of controlling a diesel helper from a steam locomotive?
As noted in the other thread on the topic, it would appear that the problem was the unanticipated loss of control from the custom-built controller in 844.
It’s common for steam movements on the mainline to have a Diesel as “protection power.”
There are probably a number reasons they had power on the Diesel - a grade of some sort being the most logical - perhaps so they could maintain speed instead of slogging up the hill.
Given that they’re going to have to drop all four axles, I’m sure they’re going to make sure it never happens again.
We should probably count ourselves lucky that UP isn’t deciding it isn’t worth the trouble and expense, and mounting/stuffing 844.
When in the cab of the 3985, I asked about the ability to control the diesel helper, and was shown a solid state circuit system that translated the throttle setting of the steam locomotive into the same signal used between two diesels…the 3985 has normal MU cables and receptacles on the tender.
I would hazard a guess the 844 has the same system.
I had imagined a DPU or Locotrol system, but was told it was not necessary, as any helper on the rear of the train would have to be manned, and could only be used if the passenger cars were empty, (no passengers) so setting it all up as a normal MU system was the only real alternative.
As for the brakes, the train line, main reservoir, aux and independent all hook up the same as between two diesels MU’ed, so an assumption, ( the freedom to guess) is that the throttle “box” failed, and if they had passengers riding, and were in no immediate danger, so the crew would not have put the train into emergency, but would have tried the 844s independent to slow down, and considering it has cast iron brake shoes, which heat up and grab much better than composite shoes, the tendency of the drivers to lock and slide seem more possible.
Last guess, I would imagine they slowed down enough for a crew man to drop off, mount the diesel and gain control.
All of the above considered, it seems to me the crew did the best thing possible under the circumstances.
You can see the brake pistons extended on the trailing truck of the second auxiliary tender and on the trucks of the diesel. You can also see smoke coming from the trailing truck of the diesel. On another version of this video with sound, you can hear the diesel running at a fairly high throttle.
In an emergency like this, would the rules against being on the top running boards of moving rolling stock have forbade the crew from crossing over the tende
I don’t know. I have seen that question posed by others and the answer seems less than straight forward because of what effect the diesel might have had in its M.U. relationship with the controller.
But if dumping the air would not have shut down the diesel, the engineer would seemingly have had to know that ahead of time. Otherwise he would have dumped the air. I assume he did not dump the air. I wonder if the brakes were set on the cars behind the helper even though not in emergency.
It would seem that setting the brakes too hard on the train would have had the diesel pull a drawbar. And if they did that and left most of the train behind, the diesel might have been even harder to stop or slow down to the point where somebody could get to it from the ground.
But since this whole thing probably happened in the space of a couple minutes, there probably was not enough time to think through all the possibilities.
So then why do you think the engineer did not put the brakes into emergency and solve the whole problem right away?
My only point about the diesel pulling the train in two if the brakes were fully set is that it would have suddenly relieved the diesel of the burden of pulling the train, and thus given it extra ability to shove the steamer down the track.
I don’t know - I wasn’t there, nor am I him. Maybe they did dump it, maybe they didn’t. Maybe they were in panic mode, or maybe they were completely calm and used other means. Who knows? We can only speculate and pee into the wind on this one.
I don’t mind speculation. We are under no official responsibility to find the actual facts, and I would not be surprised if we are never told. And our discussion cannot change the facts or hurt an objective investigation by the people in charge. So for here and elsewhere, it is only a topic for academic discussion. But we do know the fact that this extremely unusual event did occur. And I would speculate that it has raised some important eyebrows at U.P. I’ll bet they are speculating.
And I would speculate that if somebody posed this scenario of an unstoppable fantrip auxiliary diesel as fiction, we would be told that it could not happen because of all the remedies and safety measures.
The PCS only trips on the lead engine of a consist and then the signal to go to idle is transmitted to the trailing engines in the consist. I don’t know how the MU works between the UP’s steam engines and trailing diesels. The steam engines I don’t think have a PCS and I don’t know if the controller has something to compensate for that or not.
I read on one of the links that the UP controller has a MU shutdown capability. If that didn’t work it’s possible that no control signal of any kind was getting to the trailing engine. The problem could be in the control box, the MU cable/plugs, or even something on the trailing engine.
I like reading (here and elswhere) about whether the problem is a mechanical/electrical one or crew error. One posting even theorized that the pilot engineer was running. Another gave the impression that since Steve Lee retired, the whole steam crew now consists of amatuer newbies who don’t know their, well you know what I mean.
I doubt very much the pilot engineer was running. I haven’t been a pilot on a steam move (yet), but some of my coworkers have. One asked if he could have a try at it. The answer was a polite, but firm NO. I’m sure also that the remaining steam crewmen know what they are doing. If something happened, it’s probably something of a mechanical/electrical nature that they handled about as well as anyone could.
Even though I think it was an equipment problem, I can’t help but think that being the steam engine and crew involved that they get more benefit of the doubt about it being an equipment failure than a human one. If it were a regular freight crew involved they’ld probably go out of their way to try to prove it was operator error rather than an equipment failure.