Challenger No. 3985

Occasionally Union Pacific has some cool trains go on tour and they come through Iowa. We went up to Boone, Iowa to see this one. It is the Challenger No. 3985. It was designed by Union Pacific and built in 1943 by the American Locomotive Company. It is one of 105 Challengers built for Union Pacific between 1936 and 1943 and is the only operating engine of its class in the world today – the largest and most powerful operating steam locomotive.

Here's a cool picture from the front. Miya was so cute when we got out of the car she kept saying, "oooh, look at that!" It made me laugh.


Aaron and the kids with the locomotive from the side. I kept trying to get Miya to look at me but she couldn't tear her eyes away from the train. It's so big that the frame of the locomotive is articulated, or hinged, to allow it to go through curves.


Spencer was really facinated with the big wheels and all the steam coming out of the train. Here he's showing me the steam and dripping water. He said, "the train needs go potty".


Here's the cab I like how you can see into the boiler.


I don't know if Aaron or Spencer had more fun checking out the trains. Aaron kept telling him about everything they were seeing and how everything worked. Spencer was listening intently and would occasionally ask questions or say, "that's so cool!"


I just liked this cute picture of my little Miya walking next to the train.


I wanted a picture taken next to one of these huge wheels. They seemed really cool to me because I had just read about them online. Here's what I found out... "The name Challenger was given to steam locomotives with a 4-6-6-4 wheel arrangement. This means that they have four wheels in the leading "pilot" truck, which helps guide the locomotive into curves; two sets of six "driving" wheels, and finally, four "trailing" wheels, which support the rear of the engine and its massive firebox. Each set of driving wheels has its own steam cylinder. In essence, the result is two engines under one boiler."


Here's a picture to show how big these wheels really are. Spencer looks so tiny!