I ran across this on another site.

"Update 4-26-12

I have talked to the STUDENT ENGINEER this morning,( a friend for 25 years) and this is the account of what happened.

The train was coming to a station stop about 2 miles out and brakes were applied as normal. He was in the engineers seat and the engineer was at the fireman controls. There was a road foreman in the cab also. The 1982 EMD SD70Ace, however did not throttle down. It was in run 6. It should be noted that the crew reported the diesel was acting strange earlier in the day, it would throttle up on it's own. More brake pressure was applied, and still the diesel kept pushing away, with brakes on. The engineer now with the student engineer pulled the emergency brake. The train went into full emergency, but the diesel would not throttle down, and kept pushing long after the PC switch should have opened. Now full panic in the cab, the student engineer was told to use a small amount of reverse throttle to try and stop the train, and this was a last resort, as everything else was tried. The SD70, finally dropped to idle, about 2 full minutes after the first brake application. The 844 drivers slid about 12 to 20 feet and took about 1/16 metal off the drivers as a flat spot. No sand was used. I asked about the 'Mountain cock" that Jack described, and he had no idea what I was talking about. He didn't know there was a valve to cut out the driver brakeshoes. Full brakes on the drivers.

It was noted in the diesel cab, the reverser was in center position and the throttle was in idle.

It was, as I suspected in my first post, a mechanical (in this instance, computer) problem.

The tape from the 1982's 'Black box' confirmed that the control was operated properly, but the diesel engine control did not respond. The unit is in North Little Rock until they find what malfunctioned.

The Good news is the steam crew expects (BTW, no one was fired) the 844 to be completed by mid to late next week, as 2 sets of drivers were sent to Pennsylvania, and the other 2 sets were sent to Kentucky to speed the turning driver time and reinstall the drivers ASAP to get the loco back out on the road."

You can read all the discussion at:

http://ogrforum.ogaugerr.com/displayFor ... 135/page/1

Wouldn't the field switch on the box have killed power instantly regardless of anything else? Did they use it?

Steve

I wouldn't worry about it. Everybody knows that these new computer controlled locomotives are smarter than their operators. Problem is 844 just didn't know it should keep going. The SD70 was trying to tell it to keep going, but it just didn't want to listen.

Cynical comments aside, I would always prefer my engineer to be smarter than my locomotive. I want a locomotive to do what its told, not think about what I'm telling it to do and determine if it agrees. Sounds like the UP folks were doing all the right things. Maybe next time they need a "dumber" diesel. A couple of nice Armour Yellow GP-30s might look good back there helping.

Sorry, but I don't quite buy that story. I really have a hard time believing a story with an unnamed source, and I also have trouble believing that the "STUDENT ENGINEER" would have told anyone outside the company what went on.

Also, the whole story about not knowing the drivers have a valve to cutout the brakes, what's that about? The engineer could have very easily bailed the brakes and achieved the desired effect.

The kicker of the story is, "It was, as I suspected in my first post, a mechanical (in this instance, computer) problem." LOL!

In a later post he mentioned the "STUDENT ENGINEER" has been a road conductor for 5 years. I've seen stranger things, but I cannot imagine UP would promote someone who has no experience as an engineer to run on the Steam Program. Lord knows theres probably a line of experienced engineers wanting a chance to run, so why promote someone who is just a conductor?

Steve is exactly right in his posting (third post back), shutting off the generator field switch on the diesel box in 844 would drop out the generator field contactor on the diesel and take it out of power regardless of what the other MU circuitry is doing with control of the diesel prime mover.

I agree with jcmark611, that report is very questionable, another thing about it that just screams out at you is the bit about the crew having trouble with loss of control of the diesel earlier in the day. If so, why was it left running when 844 was capable of handling the train on its own.

PC

"Now full panic in the cab, the student engineer was told to use a small amount of reverse throttle to try and stop the train, and this was a last resort, as everything else was tried. The SD70, finally dropped to idle, about 2 full minutes after the first brake application."

Re-reading, I think perhaps it is rotten info here. In my mind there were some steps skipped between what was tried and the 'last resort". Emergency Stop button, low oil button on the governor, or even the layshaft would kill it. Certainly you would think that the event recorder would shed some light on what went on, probably the day of. If no one from the crew is "out of service" then I would think that lends credibility to the theory of a mechanical problem or failure. Even more so if 1982 has been dispatched to the shop at North Little Rock.

I think someone mentioned this elsewhere, but the UP motors do have a 20 second delay in the PCS between the emergency application and the unit dropping power. The other random thought for the morning is that reversing a diesel in motion tends to be quite violent, unfortunately something I've witnessed first hand.

ETA

I've had a "first hand" experience with a SD70ACe not responding to throttle command. It was a trailing unit of a DP Remote consist. The two other engines dropped to idle when train was stopped, while the SD70 stayed in Run 6. Burned half way through the rail! Download of the computer showed the wheels reach a speed of 83 mph, but the overspeed set for 73 mph did not trip the PCS.

BTW, the SD70MAc's have electronic governors without the "Low Oil Button" and no layshaft.

According to that report, the engineer put the brakes into emergency, but the diesel kept shoving the train ahead.

For some unexplained reason, the PCS did not take the diesel off line as a result of the train’s brakes being put into emergency.

The report actually does not explain how the diesel was taken off power. It says that as the last resort, the steamer shoved back in reverse, and the diesel finally dropped to idle. But shoving back would not have idled the diesel. At best, it would have only stalled the train. So the report reads as though the diesel just sort of gave up on its own.

Or maybe somebody shut off the generator field switch on the diesel box?

PC

I'm not going to comment on the veracity pf the story, other than to say that it sounds questionable to me... but I do think we need to keep in mind, whatever happened while it was happening, preventing flat spots on the drivers would have been of pretty low on the priority list, waaaay down below getting the train stopped before someone lost their life. Yeah, bailing the independent would have released the driver brakes, but if you look at the consist, the locomotive consist is approximately half the total weight. Bailing the brakes would have decreased braking capacity by about half, and I'm sure at that point, was simply not an option. Given the situation, flat spots are just a little annoyance. Since it appears that no one got any time off due to this incident, it appears the UP agrees.

What if...and I hope you're sitting down...we never find out? Can we handle it? ;)

Steve

Blasphemy!!!!

I thought we lived in a world where we have "the right to know" everything and anything ...about anything and everything?... Like what the 3rd cousin of the back up engineer's sister in law's aunt from her grandfathers third marriage, had for breakfast that day!?


Steve, you speak evil words!

As far as any longer term corrective actions are concerned, the Union Pacific certainly will "Handle It" just as the slogan on their equipment used to say, and probably has already done so. But yes, the results of the download from the diesel would be interesting.

PC

It depends on whether U.P. wants to explain what happened to set the record straight. If not, the public will be perfectly satisfied with their own explanations.

Indeed the download would be interesting. I was going to say it's too bad there's no data recorder on the steam engine but then again, that's only if the spoken account by those who were there was in question. But either way, we fans may never know.

Obviously, the UP doesn't owe anyone an explanation and we are all very thankful they even have a steam program.

You do kind of wonder though, if the diesel kept on pushing for whatever reason and crew took the best possible course of action for the safety of the train & the public, and finally, the locomotive, that they would have, by now, issued a statement for those interested, just to lay the matter to rest. But if the facts suggest a somewhat embarrassing lapse that could have avoided the whole matter, like forgetting that they could kill the generator field, that would be a good reason to simply say nothing.

I am not suggesting any such lapse whatsoever took place. Only that we don't know but then again we have zero right to know in this matter. And thus, we may never know.

Steve