Week of July 16
The area around Đà Nẵng, especially military installations, was subject to rocket attacks since that February. The area the rockets were fired from was called the "Rocket Belt". It wrapped around the base and city. The area was around 200 square miles, and the 140mm rockets had a range of over 6 miles. The Rocket Belt was kept under surveillance from the air and on the ground.
In July of 1967, the North Vietnamese and Viet Cong had a new advantage to exploit in their attacks on the Đà Nẵng Airbase. For the first time in South Vietnam, they would employ 122mm rockets with a range of 7.5 miles. They were delivered to a staging area just outside of the Rocket Belt southwest of Đà Nẵng nicknamed "Happy Valley" by American forces.
The rocket launchers, relatively light, were broken down into portable pieces the men could carry, along with their ammunition. The rockets could be fired from simple improvised launchers, although with less accuracy. Launchers could be set up in a half-hour and in typical attacks, each launcher could fire several rounds and quickly moved.
On the night of July 14, the new 122mm launchers were set up in six batteries, each with six launchers. Just after midnight on July 15, the first rockets were fired at the airbase. In five minutes, they had expended their ammunition. Between fifty and eighty-three heavy rockets hit the base. Within minutes of their first shots, Marine artillery and an airborne Air Force plane fired on the positions.
Across the length of the field, the impact on the base was extensive. Eight American servicemen were killed in the attack and 175 were wounded. Five of those lost were United States Air Force firefighters of the 366 Civil Engineer Squadron. They were killed in the secondary explosion of a bomb on a burning F-4 Phantom that they were trying to extinguish. Ten aircraft, 13 barracks, and a bomb dump were destroyed. Forty aircraft were damaged. The Air Force reported one and a half million dollars in property losses.1
1Spencer Tucker, The Encyclopedia of the Vietnam War: A Political, Social, and Military History (Santa Barbara, ABC CLIO, 2011) pp 257-8. Kieth Flemming, The U.S. Marines in Vietnam 1967 - Fighting the North Vietnamese (Washington, DC, History and Museums Division Headquarters USMC:1984) pp222-3. William Thorndale, Project Checo Southeast Asia Report - Defense of Da Nang (USAF, HQPA,CAF 31 August 1969) p13 - 15.