Operation Market Time: Coastal Interdiction in Vietnam

Operation Market Time was a coordinated naval operation involving the United States Navy, the Republic of Vietnam Navy (RVNN), and the Royal Australian Navy. Launched in 1965 during the Vietnam War, its primary objective was to block the transport of troops, supplies, and war materials by sea, coast, and rivers from North Vietnam to South Vietnam.

To facilitate coastal surveillance, Coastal Surveillance Centers (CSCs) were established in key locations, including Da Nang, Qui Nhon, Nha Trang, Vung Tau, and An Thoi. Manned by RVNN and U.S. Navy personnel, these centers coordinated responses by dispatching vessels and aircraft to investigate reported sightings from patrol craft and reconnaissance aircraft.

The operation officially began on March 11, 1965, with the goal of preventing communist forces from resupplying via the South Vietnamese coast. Over 1,000 miles (1,600 km) of coastline were patrolled by U.S. Navy ships, U.S. Coast Guard Cutters, and RVNN vessels. Initially controlled by the Vietnam Patrol Force (Task Force 71), command shifted on July 31, 1965, to the Commander, Naval Forces Vietnam, as Task Force 115.

Originally planned to involve 54 Swift boats, the fleet expanded to 84 by September 1965. These vessels were divided into five divisions, each assigned to different operational areas:

• Division 101 at An Thoi (with Coast Guard Division 11)
• Division 102 at Da Nang (with Coast Guard Division 12)
• Division 103 at Cat Lo (with Coast Guard Division 13)
• Division 104 at Cam Ranh Bay
• Division 105 at Qui Nhon

Seaplane tenders such as USS Currituck, USS Pine Island, and USS Salisbury Sound served as operational flagships. The U.S. Navy employed a variety of vessels, including destroyers, ocean minesweepers, PCFs (Swift boats), and patrol gunboats (PGs). The PGs were particularly effective due to their speed, maneuverability, and versatile propulsion systems.

Aircraft were integral to the operation. Early on, Martin P-5 Marlins provided aerial reconnaissance, later replaced by P-2 Neptunes and Lockheed P-3 Orions equipped with Bullpup air-to-surface missiles. These aircraft monitored vast coastal waters, relaying intelligence to surface forces for interception.

On March 1, 1968, a coordinated infiltration attempt by four North Vietnamese trawlers resulted in a significant engagement. Allied forces destroyed two trawlers in gun battles, one vessel was scuttled by its crew, and the fourth retreated. Lieutenant Norm Cook, a patrol plane commander, was awarded the Distinguished Flying Cross for tracking two trawlers during this action.

Another notable incident occurred on August 11, 1966, when the U.S. Coast Guard cutter Point Welcome was mistakenly attacked by U.S. Air Force aircraft. This "friendly fire" incident killed two crew members, including the commanding officer, and wounded nearly everyone aboard.

By October 1967, air surveillance extended to Cambodian traffic, as supplies were being shipped to Sihanoukville and then transported by truck convoys to South Vietnam. Aircraft patrolled 1,200 miles (1,900 km) of coastline, departing from bases such as Tan Son Nhut Airbase and Cam Ranh Bay in Vietnam, Sangley Point in the Philippines, and Utapao Airbase in Thailand.

Participating U.S. Navy patrol squadrons included VP-1, VP-2, VP-4, and many others. Although aerial operations received little media attention, their contribution was crucial in monitoring and interdicting enemy supply lines.

Operation Market Time played a vital role in countering maritime supply routes, demonstrating the effectiveness of coordinated sea and air efforts in disrupting enemy logistics.