The classifications given by railroads to their steam locomotive fleets were as varied as the machines themselves with several different designations within a particular class! While a rather small fleet Missouri-Kansas-Texas steam locomotives were likewise distinguished by a number of classes from A to L. In any event, the information here is most certainly not a complete, all-time listing of the Katy's steam fleet and also is merely meant to list the general types of steam locomotives operated by the railroad.
The Missouri-Kansas-Texas Railroad, better known as simply "The Katy" or "K-T Railroad," was a large granger system that, like the Illinois Central and Gulf, Mobile & Ohio ran, unconventionally, north-south (instead of the more common, east-west).
As its name implies, the Katy connected all of its namesake states with connections to cities such as Omaha and St. Louis in the north and Galveston and San Antonio, Texas in the south. The railroad was somewhat successful over the years but it ran into financial trouble a number of times throughout its life. As finances again became an issue in the 1980s the MKT sought a merger with the Union Pacific in 1986 and in 1989 the Katy became yet another part of the UP empire.
While the MKT operated from St. Louis to southern Texas it did not operate a very large steam fleet with its largest steamers being 2-8-2 Mikados and 4-6-2 Pacifics. Today, only one MKT steamer is known to exist, a 4-4-0 American preserved on display at the Museum of Transportation in St. Louis.
Class C
The Katy's Class C included its roster of 0-8-0 switchers.
Class D
The Katy's Class D included its roster of 2-6-0 Moguls.
Class H
The Katy's Class H included its roster of 4-6-2 Pacifics.
Class L
The Katy's Class L included its roster of 2-8-2 Mikados.
Other steam locomotive types to operate on the Katy include 2-10-0 Decapods (provided by the USRA during World War I), 4-4-2 Atlantics, and 4-4-0 Americans.
For more reading on steam locomotives like those operated by the Katy consider Perfecting the American Steam Locomotive by author J. Parker Lamb. As the name implies the book details the earliest history of steam engine technology, even before it was used in railroad applications. His book later explores the development of steam locomotive technology in the United States from the 19th through the 20th centuries, covering not only the most popular steam locomotive designs but also the most successful manufactures to build them. The book has received excellent reviews and is a great resource on steam locomotives and a fine reference tool; you should find it very useful.
Also, consider the book American Steam Locomotives from author Brian Solomon. While this publication does not include quite as much technical data as Lamb's book, Perfecting the American Steam Locomotive, it is still a very good resource with lots of information and best of all, is loaded with photographs! If you're interested in perhaps purchasing either (or both) of these books please visit the links below which will take you to ordering information through Amazon.com, the trusted online shopping network.