Military Region 6 encompassed the southern provinces of II Corps — Ninh Thuận, Bình Thuận, Tuyen Duc, and Lâm Đồng — plus Bình Tuy Province in northern III Corps. It was controlled by General Nguyễn Minh Châu, who commanded four Viet Cong battalions and approximately six district-level companies. The region had seen little sustained combat before 1966. Its small population and dry terrain made it a lower priority for both sides, which paradoxically made it valuable to the Viet Cong: the absence of heavy Allied presence allowed them to build a durable organizational network among the rural communities. When the 2nd Battalion, 7th Cavalry deployed to Firebase Betty, south of the provincial capital Phan Thiết, on 25 August 1966, they were entering territory where the enemy was organized, familiar with the terrain, and prepared to fight on its own terms.

The early phases of Operation Byrd were marked by the kind of success the official record keeps cleanly: over 250 Viet Cong killed in the initial search and destroy phase, with minimal Allied losses. But the operation's most tactically interesting chapter came later, during a VC attack on an ARVN outpost. Lt. Col. Joseph T. Griffin Jr., commanding Task Force Byrd, responded with a Night Hunter team — three UH-1 helicopters working in coordinated formation. The first flew low to the ground, its infantry armed with Starlight scope rifles that turned darkness into dim green visibility. The second dropped flares from altitude, flooding the terrain with white light. The third stood ready to respond with aerial rockets. An AC-47 Spooky gunship arrived to complete the firepower overhead. Together, they held the Viet Cong at bay through the night until a ground company arrived at dawn. It was Vietnam War aviation at its most ingenious — complex, layered, and improvised in real time.

The operation's costliest engagement came on 22 November, when Viet Cong forces launched a mortar attack on an ARVN outpost at Thien Giao. Griffin sent a platoon by helicopter to engage. When the aircraft descended toward a clearing near the outpost, the VC 482nd Battalion was waiting. The ambush had been planned specifically for an air assault response — the enemy had anticipated the move and positioned machine gun teams around the landing zone. Two helicopters were forced to crash-land under fire. Griffin sent the rest of the 2nd Battalion to relieve the stranded platoon; those aircraft flew into the same wall of fire. When the fighting ended, eleven Americans and twenty-eight ARVN soldiers were dead, with scores more wounded. The 482nd Battalion eventually disengaged, leaving its own dead behind. The engagement at Thien Giao was a reminder that the Viet Cong understood the tactics being used against them and had learned to turn those tactics against their users.

Operation Byrd was suspended on 1 December 1967 — not concluded in any decisive sense, but handed off. The 2nd Battalion, 7th Cavalry moved north to join the 1st Brigade, 101st Airborne Division, in Operation Klamath Falls along the Bình Thuận–Lâm Đồng border. Operation McLain, conducted by the 3rd Battalion, 506th Infantry Regiment, took over the security mission in the province. The handoff was typical of the war's logic: operations ended on paper while the underlying conditions persisted. The communities of Bình Thuận Province — Vietnamese farmers, Cham people, highland minorities, soldiers on both sides — continued to live through a conflict that had no clear end visible from any position on the ground. Operation Byrd is a record of that experience: sixteen months of helicopter operations, night fighting, ambushes, and the particular exhaustion of securing a countryside that did not want to be secured by either side's methods.