The besieged Marine fire base was supported by OPERATION NIAGARA in early 1968, which supplied 24,000 tactical sorties and 2,700 B-52 sorties.  Airpower dropped over 110,000 tons of bombs on the enemy over a two-month period. Additionally, Seventh Air Force Commander, General William Momyer, was made the single manager for air. Under this centralized control concept, Momyer made effective use More..of all Air Force, Navy, and Marine tactical air units in support of Khe Sanh. The North Vietnamese were forced to lift the siege in March 1968.