US 5th Armored Infantry

From Memory Alpha, the free Star Trek reference.

The 5th Armored Infantry, according to a holonovel simulation of World War II stored in the holodeck of USS Voyager, was a division or unit of the Army of the United States during that 1940s conflict.

The holographic characters who identified themselves as being part of the 5th, under Captain Miller, wore the assignment patch of the US 29th Infantry Division. (VOY: "The Killing Game", "The Killing Game, Part II")

In reality, there was no 5th Armored Infantry unit as part of the 29th in WW2's European theater of operations, although a division with a similar name took part in the conflict. If this was truly intended to be a fictional unit in a realistic interpretation of the war, it is possible it would be referred to as the US 5th Armored Infantry Regiment or the US 5th Armored Infantry Batallion However, there was a US 15th Armored Infantry Batallion serving withe the US 5th Armored Division, and a US 50th Armored Infantry Batallion serving with the US 6th Armored Division.