From Just Solve the File Format Problem
These are file formats related to military and national-defense matters. Presumably there are many of these that are classified, but there are also some that are publicly documented.
- BRL-CAD geometry (originated at the U.S. Army Ballistic Research Laboratory)
- NIFF (Navy Image File Format)
- Standard Archive Format (used by the U.S. Air Force for archiving missile data)
More formats might be listed in Category:Military.