 As the Army began reorganizing for new missions, many Vietnam-era units and missions changed shape.The 1st Cavalry Division became a test division for the TRICAP concept (a division that could perform armor, airmobile, and air cavalry missions simultaneously), and later shifted to an armored division.The 101st Airborne Division retained an airmobile (later air assault) role, but during the various reorganizations of the 1970s its AFA/ARA battalion disappeared.