1 April 1974 when the 101st became a completely airmobile division (renamed Air Assault on 4 October 1974). The lineage of 2-503rd was inactivated on 1 October 1983 and relieved from assignment to the 101st, followed by 1-503rd on 16 November 1984. The existing battalions were reflagged as units of the 187th Infantry Regiment during the implementation of the U.S. Army Regimental System (ARS). Reactivation in Korea, assignment to Italy On 16 December 1986 both 1-503d and 2-503d were reactivated and assigned to the 2d Brigade, 2d Infantry Division in Korea when two existing infantry battalions were reflagged. Stationed together at Camp Hovey, they formed the division's 2d Brigade, which also included the 1st Battalion, 506th Infantry. Both battalions of the 503d performed annual rotations to Warrior Base, just south of the Korean Demilitarized Zone (DMZ), from where they patrolled the DMZ; manned guard posts Collier, Oullette, and 128; and served as a quick-reaction force for the DMZ. The 2nd Bn, 503rd Inf was inactivated on 29 September 1990 in Korea and relieved from assignment to the 2nd Infantry Division, but 1-503rd and 1-506th remained and became air assault battalions within the division. (Although locally referred to as air assault battalions, they were never recognized as such by DA and were employed as regular infantry battalions.) The 2nd Bn, 503d returned to active status as an airborne battalion on 16 December 2001 when it was assigned to the 173rd Airborne Brigade and activated in Italy. The company names were kept from its lineage in Korea: A Company (Able), B Company (Battle), C Company (Chosen), D Company (Destined), H Company (Hound), HHC (Blacksheep). Global war on terror In March 2003, the Turkish government refused to allow American ground forces, which were positioned at their ports, to move through Turkey in order to establish a northern front in support of "Operation Iraqi Freedom". America needed another option and the paratroopers of the 173rd Airborne Brigade provided that option. On 26 March at 2000 hours, fifteen C-17 aircraft delivered 20 heavy platforms and 959 paratroopers of the 173rd Airborne Brigade onto Bashur Drop Zone in the vicinity of Bashur, Iraq. This combat parachute assault was the beginning of Operation Northern Delay and established the coalition's northern front. The parachute assault force consisted of HHC, 173rd Airborne Brigade; 1st Battalion (Airborne), 508th Infantry Regiment commanded by LTC Harry Tunnell; 2nd Battalion (Airborne), 503rd Infantry