Cozzalio arrived for first time in
Vietnam in December 1967, he was deployed to the
Bearcat Base in
Đồng Nai province and was assigned to an air cavalry reconnaissance unit (D Troop, 3rd Squadron,
5th Cavalry Regiment) attached to the
9th Infantry Division. The unit wore yellow scarves and white
Stetsons, evoking the uniform of prior-era horse cavalry units. Cozzalio served as a “War Wagon” pilot, flying the small, two-man
OH-6 light observation helicopters—nicknamed Loaches—used for low-level reconnaissance and rapid engagement. In his second tour, he flew
Huey Cobra gunships. Citing his skills as a pilot and leadership experience, the unit's commanding officer placed Cozzalio in charge of the Crusader gunship platoon He was first shot down in December 1967 after his first 18 hours of piloting in Vietnam, where Cozzalio suffered a broken jaw after crashing, which required a six-week hospital stay, he was treated at the 106th General Hospital in Yokohama, Japan before returning to duty. On 10 April, Cozzalio became the Aero Scout Section Leader, during which he participated in the
May Offensive in Saigon's
Cholon sector from May 5 until May 11, 1968, providing critical gunship support during the intense fighting. On May 10, the D Troop along with the 3rd Brigade, 9th Infantry Division, was credited with killing 13 enemy combatants during separate engagements throughout the day. On May 17, he was assigned as Aero Scout Section Commander. In recognition of their valor, Delta Troop was awarded the
Valorous Unit Award, one of the U.S. Army’s highest collective honors for heroism in combat. The official citation praised their “extraordinary heroism and devotion to duty,” crediting their actions with helping to prevent an enemy breakthrough into the capital. His service included two required six-month tours, during which he received 49 medals including a
Silver Star, three
Distinguished Flying Crosses, the
Soldier's Medal and two
Purple Hearts, one for a bullet wound to the neck and another for a broken jaw, suffered after crashing when shot-down, which required a seven-week hospital stay before he returned to duty. He logged over 1,000 hours of combat flying in the area around
Saigon. Flying both Cobra gunships and the
Hughes OH-6 Light Observation Helicopter (Loach), he preferred the fast and light Loach and was reportedly the first to arm one with machine guns for offensive operations. After his twelve months active duty in Vietnam, he took a 30-day leave at his home in Oregon before a voluntary return for an additional six-month extended tour.
United Press International reported that his exploits were "practically legendary" and "far surpass those of the
Lone Ranger and Silver". On January 25, 1969, seven days after his voluntary return to Vietnam, he was awarded, "on the spot", a second Silver Star and promoted in the field from
first lieutenant to
captain by a general who had observed Cozzalio's assault on an enemy bunker. The incident was part of the
Battle of Phu My, where Cozzalio spotted the entrenched enemy position while flying a Cobra gunship. He landed his helicopter and "commandeered" a more maneuverable Loach. "With gallant disregard for his own safety", Cozzalio destroyed the target while hovering a few feet above. He landed to brief the ground forces commander on his view of the battlefield, then resumed flying to direct and support the infantry. He was later awarded the
Distinguished Service Cross for this action. Cozzalio spent eighteen months in Vietnam and was shot down a total of six times. Several times, he returned in a helicopter so badly damaged it was never flown again. Despite being one of the "most highly decorated" soldiers of the Vietnam war, he did not return for a fourth tour for "straying too many times across the
Demilitarized Zone. Over his three tours, he accumulated over 2,100
flying hours in the OH-6A,
Bell UH-1 Iroquois,
Bell AH-1 Cobra. ==Postwar (1972–1986)==