The West Point Tartan is actually fairly old; I believe it dates back to the 70's or 80's. I'll have to check my Company of Military Historians plate of the West Point Pipes & Drums and see when it was adopted.

The US Naval Academy Pipes & Drums wear the Polaris tartan, and they have been around since the 1960's. I also have another CMH plate of the US Air Force Reserve P & D when they were wearing the Mitchell tartan (in honour of Gen. Billy Mitchell), and before they adopted their present tartan.

Cheers,

Todd