6-4-4-4

The 6-4-4-4 wheel arrangement was a proposed wheel arrangement for a steam locomotive, in the Whyte notation for describing locomotive wheel arrangements, is one with six leading wheels, two sets of four driving wheels, and four trailing wheels, much like the 4-4-4-6 but reversed in the opposite direction.
=== Other equivalent classifications are ===
* UIC classification: 3BB2 (also known as German classification and Italian classification)
* French classification: 3222
== Santa Fe 6100 ==
The Santa Fe 6100 Class would've used the wheel arrangement of 6-4-4-4 as confirmed in "Iron Horses of the Santa Fe Trail" in Chapter 23 "Iron Horses That Didn't Make the Trail".
The designs in the drawings suggest it would use either a shark-nose similar to the Pennsylvania Railroad T1 and Baldwin RF-16 or a design similar to the EMD E and F units for the cab design, the cylinders would be faced similar to the Pennsylvania Railroad Q1's cylinders, it would've been built for the ATSF's Super Chief, however it was never materialized possibly due to:
# Diesels were rapidly taking over steam locomotives in America, the idea/notion of investing another steam locomotive wasn't a good idea, so the Atchison, Topeka and Santa Fe had wounded buying a bunch of diesels, as did pretty much every other railroad company.
File:SantaFe6100drawing1.jpg|A drawing of the Santa Fe 6100.
File:SantaFe6100drawing2.jpg|Another drawing of the Santa Fe 6100.
== External links ==
* Cs.trains: https://cs.trains.com
Category:6-4-4-4 locomotives
Category:Wheel arrangements
Category:6-4-4-4 steam locomotives
Category:Unbuilt locomotives