Complex sentence: The United States Air Force (USAF), in a manner similar to the U.S. Army, the term "executive officer" (XO) in the U.S. Air Force is not a command/second-in-command position.
Split into simpler sentences: The United States Air Force (USAF) uses the term "executive officer" (XO) in a manner similar to that of the U.S. Army. In the U.S. Air Force, the XO is not a command or second-in-command position.