There is only one file type that uses the .LTB extension:
LithTech Binary File
File created for LithTech Jupiter, a graphical video game engine; contains graphic models such as weapons, characters, maps, and textures referenced for developing games like "F.E.A.R." and "Combat Arms."
NOTE: LithTech Jupiter Ex was released in 2005 and remains the latest engine release. It was last developed by Touchdown Entertainment, which was formerly known as LithTech, Inc. (which was developed by Monolith Productions).
Updated: November 12, 2013