This video describes the backbone and development of the Union Pacific's freight hauling operation... The 9000 Class or also known as the Union Pacific.
During my railfan trip (from home in UK) to California and Arizona I climbed up on the footplate of 9000 at Pomona. Big Boy 4014, then still a non-runner, was in the same yard. Two fantastic locos in one place! The inside cylinder and valve gear of 9000 seemed hardly accessible. I wonder how they maintained it, and what kind of language the fitters used while struggling. The Gresley derived motion was a joint design by Gresley and Holcroft, but Gresley was Chief Mech Eng at the time. There were always plenty of 3-cylinder and 4-cylinder steam locos in the UK, at least up to WW2, but the 9000 is the only US 3-cylinder I know about. Many thanks for reminding me of Pomona!
big thanks for this one, the UP 9000 is one of my favorites, the distinctive off beat exhaust is unique and this was a very successful class which is unusual in a one off class of individual wheel arrangement and cylinder layout - video of the 9000’s seems to be quite rare but there was a class of three cylinder 4-8-2’s here in Australia, the 57/58’s that were caught on film and to hear them on a heavy load is music to my ears. thanks again for this 9000 video
I knew about the Challengers, Big Boy, the notably earlier No. 119 4-4-0, and the later gas turbine along with their attempt at steam turbine (GE steam turbine) and the DDA40X. Yet I never knew about this one.
Putting the air pumps up front w/that high-mounted headlight gave them a mean look like they could handle whatever you coupled up to them, but that certainly didn't turn out to be the case. That 3rd cylinder had to be a bitch to work on.
One successful example of a locomotive with more than 10 coupled wheels. There were other 12 coupled locomotives in existence, of which one was built for the Pennsylvania Railroad for use as a pusher. Most others were built for Austria and Bulgaria spread over several classes, both very mountainous countries, some were rack locomotives too for when on the steepest sections even 12 coupled wheels weren't enough. Then there have been some examples used in Germany, France and Java, an Indonesian island. All of these had drivers considerably smaller than those of the 9000s, so that they could traverse the tighter curvature on mountain railroads.
@@TheRailroadCrossing-SteamPower I haven't found much of the numbers as in the central European praxis hp figures were mostly mentioned in the statistics rather than maximum tractive effort. For most of these locomotives however a low axle load was the reason for the 12 coupled drivers, they were mainly built somewhere between 1910 and 1925 when the track was not yet adapted for axle loadings between 19 and 21 metric tons, later decapods with these axle loads were actually more powerful than these. The Bulgarian BDZ class 46 2-12-4 tank locomotive was the only one with starting tractive effort mentioned at 306,7kN or 67,616lbf, there is a preserved example in working condition, the only 12 coupled locomotive to be so in the world at the moment. So UP, what about the #9000 as the next project?
I always thought the 9000s would have been better as a 4-10-4 with a larger firebox and slightly larger drivers. Fun to think about.... Cool video, thanks much!
Why doesn't Union Pacific pull one of these out , and restore it to a runner ? I think along with the Big Boy , and the other a 4-8-2 , I believe ? the spectacle of this 4-12-2 would be astonishing to all who would view it running again. Just an idea Sir. 🤔
As cool as it would be for it to run again, The Union Pacific couldn't tour their entire network with the locomotive like they could with 844, the challenger, and the Big boy. They'd only be able to run the locomotive between Cheyenne and Omaha.
I thought the 9000s could only do the run from Omaha to Cheyenne cause do to the size of the rigid frame couldn't make the winding turns of the mountain grades but could haul tons across the plains? I could see maybe to Ogden but I think you mixed some of the light Challenger info with the 9000 info.
@@TheRailroadCrossing-SteamPowerHolcroft gear (patented 1909) predates Gresley's (1916). It's mathematically identical in terms of the way the mechanical addition is done, but differs from Gresley in where on the two outside gears it actualy takes its drive inputs from. Holcroft is more slightly more complicated to arrange, but inherently stronger and more rigid, and not subject to errors due to thermal expansion. Gresley uses essentially the same system of levers to do the maths but attaches them directly to the valve spindles, driving one from the other two, and is notorious for overworking the middle cylinder when worn. I'm pretty sure that the biography of Gresley in Master Builders of Steam (written by OVS Bulleid's son, who knew all these guys personally) emphasises that Gresley personally acknowledged Holcroft as originating the concept, even though his own patent was different enough to be granted, but I can't find my copy. Holcroft also invented a 4cylinder conjugating gear that would drive two inside cylinders from the two outside gears, but arranged to offset them and give 8 rather than 4 beats per revolution. Wikipedia has a pretty decent page under "Holcroft Valve Gear". From memory, I think the UP 9000's (and the 4-10-2 that preceded them) all had the Gresley version of the gear as originally built.
Those are the cross compound air compressors. It is a similar setup to the C&O Allegheny. There are some others that have them too. Sometimes they're referred to as "flying airpumps".
I would have loved to see a latge 4-13-12-4 with 67.5 inch drivers 330 osi 29×34 cylindrrs and a 165 ft2 firebox grate area. And number 8000 classified FTTF-1
@@paullangford8179I understand that it was the limit. It’s because it went around tighter curves and Russia didn’t have a lot of successful railroads. Russia has a history of unsuccessful railroads.
While I would like to see one in operation. I think 9000 is better as a static display. They should instead create a new build 9000, without the third cylinder, and use that for excursions.
Figures on that I do not have.. But by default, with the advances of technology, the BB and Challengers would be more cost effective overall to operate. That, and also when you consider the cost to modernize the 9000's to near or similar standards.
The AA-20 was too long for the curves, and so badly designed in detail it was basically unfixable. You might design a different 14-coupled that worked, but yard switches would always be a problem, and it would have little in common with the original. What the USSR did miss a trick on were the P34 2-6-6-2 and P38 2-8-8-4 prototypes, they were much better propositioned.
