On the 6th a combined Allied helicopter flight lifted 42 ARVN soldiers from Tarn Ky to a landing zone about 18 miles directly west of Quang Ngai. An Army UH-1B was shot down by Communist fire during the operation. Shortly after the crash, one of HMM-364's helicopters landed to rescue the crew and strip the weapons from the downed aircraft. Marine mechanics then helped Army aviation technicians disassemble the UH-1B whereupon it was suspended beneath an Army UH-37 (a twin-engine, piston-powered, heavy helicopter manufactured by Sikorsky) in a specially designed sling and helilifted back to Da Nang for repairs.
Lieutenant Colonel La Voy's squadron suffered its first combat aircraft loss on 14 April. The incident occurred after one of HMM-364's helicopters was hit in the engine by Viet Cong fire while attempting to evacuate wounded Vietnamese infantrymen from a hillside landing zone about 40 miles west of Da Nang near the Laotian border. Struck while taking off, the UH-34D plunged 150 feet down the steep hillside and crashed through the jungle into a stream bed. One Marine manning an M-60 machine gun suffered at broken leg in the crash. The other crew members and passengers, however, were able to carry him up the hill to the ARVN landing zone. Heavy thunder showers prevented rescue for two hours, but the weather finally broke and the men were helilifted to Da Nang. The aircraft was destroyed the next day.
Four days after this incident, HMM-364 committed all available aircraft to a battalion-size heliborne assault into rugged northwestern Thua Thien Province. The ARVN's objective was a mountainous area on the northern rim of the A Shau Valley, a 30-mile-long, two-mile-wide trough whose location adjacent to the Laotian border invited Communist infiltration. Although enemy activity would eventually force the government to abandon its string of outposts in the valley, the issue of control of the area was still unresolved in early 1964.
Colonel Merchant, as commander of the Aviation Headquarters Operations Center for I Corps, assigned 20 Marine UH-34Ds, four VNAF UH-34s, five U.S. Army UH-1B gunships, and three Marine 0-1 Bs to the operation which the ARVN code named LAM SON 115. Additionally, 14 VNAF T-28s, four A-1H Skyraiders, and two observation aircraft were assigned by the Joint General Staff to provide support for the helicopter assault. The operation was to be controlled by Colonel Merchant as the Tactical Air Commander Airborne (TACA) from a U.S. Air Force U-10, whose radios would permit the commander and his staff to communicate with every aircraft participating in the effort. (The Marine helicopters had UHF and VHF communications, while the Marine observation aircraft used UHF and FM. The Army UH-lBs had UHF; the VNAF transport helicopters also relied upon UHF radios.)
In addition to Merchant, the airborne control staff from the ASOC included Lieutenant Colonel William Montgomery, USAF, and a Vietnamese officer. The Vietnamese representative was to assist in clearing close air strikes with ARVN ground forces and also was to help resolve any language problems which developed.
The one-day operation began early on 18 April with Marine and VNAF transport helicopters lifting 200 South Vietnamese soldiers from an outpost in the northwestern portion of the A Shau Valley into a rugged landing zone approximately six miles further north. Later the same morning 300 more Vietnamese troops were helilifted from a government outpost in the central portion of the valley to a second landing zone situated six miles north of the 200-man unit which had been flown in earlier. HMM-364's helicopters averaged almost 8 hours per aircraft while flying 160 total hours in support of LAM SON 115. Only one Marine UH-34D and one VNAF helicopter were hit by enemy fire during the execution of the well-planned and efficiently coordinated operation. No aircraft were lost.
Often the daily support flights proved more hazardous then the large assault operations whose details were planned in advance. An incident that occurred on 21 April while a UH-34D was evacuating a wounded South Vietnamese soldier from the mountains 15 miles west of Tarn Ky confirmed the dangers inherent in such daily operations. In an effort to lure the evacuation helicopter within range of their weapons, the Communists ignited a yellow smoke grenade in a clearing close by the actual landing zone. The pilot alertly identified the correct landing zone, thereby foiling the enemy ruse.
Page 149 (The Advisory & Combat Assistance Era: 1954-1964)