The Vietnamese commanders in I Corps, who had learned to value helicopter support as a result of the Army aviation company’s eight-month presence at Da Nang, lost no time in employing the newly arrived Marine squadron. HMM-163 flew its first combat operation from Da Nang on 18 September, the day after the last flight of helicopters arrived from Soc Trang. Fourteen HUSs lifted troops of the 2d ARVN Division into two landing zones in the rugged hills about 35 miles south of Da Nang and 25 miles inland from the coast. The scarcity of suitable landing zones in the steep hill country and the fact that the enemy could deliver fire on those that did exist from nearby high ground and the surrounding jungle prompted the Marine pilots to adjust their tactics in preparation for this mission. After VNAF fighters bombed and strafed the objective area, the helicopters made an unopposed landing. The tactic of preparing helicopter landing zones with air strikes was continued and refined in the ensuing weeks. The Marines began using artillery fire in conjunction with air strikes to neutralize enemy troops in the vicinity of the objective. The OE-1 was well suited for assisting in the employment of the artillery fire support. Having familiarized themselves with the landing site during a prior reconnaissance mission, the pilot and observer of the OE-1 would arrive over the designated area prior to the operation and adjust artillery fire until the helicopters appeared. During the landing the crew of the observation aircraft often coordinated between the helicopters and the escorting aircraft and were available to assist the ground units with artillery fire missions. The task unit’s staff borrowed another idea from their experience in the Mekong Delta which allowed HMM-163 to provide more efficient helicopter support in the northern provinces. In this case the concept of temporarily positioning the TAFDS to support specific operations was refined somewhat by placing the portable refueling bladders at secure, permanent locations throughout I Corps. Several days after arriving in I Corps, the Marines emplaced a 10,000-gallon section of the TAFDS at Quang Ngai, about 65 miles south of Da Nang, to serve as a permanent refueling point for aircraft operating in southern I Corps. Within the month, another fuel bladder was positioned at Hue and a third was emplaced at Tam Ky, the capital of Quang Tin Province, which was situated on Route 1 about half way between Da Nang and Quang Ngai. These well-chosen refueling points greatly enhanced the squadron’s operational potential. Used to support daily operations, they enabled the helicopters to operate deep into the adjacent mountain areas on resupply and medical evacuation missions.