Airboat Ambush: SFC Robert Anspach's Final Mission

In late 1966, the Special Forces camps in South Vietnam's Delta region faced significant damage and operational challenges due to severe flooding. Foot patrols became difficult, prompting the use of airboats alongside Navy Patrol Air Cushion Vehicles (PACV) and helicopters for successful missions in the flood-affected areas. During the dry season that followed, the camps were rebuilt and improved to withstand future floods, while personnel focused on training for airboat and sampan patrols in preparation for the next flood season. Despite these efforts, the number of Special Forces personnel experienced in airboat operations remained limited, restricting activities to Kien Phong Province along the flooded banks of the San Tieu Giang River.

In February 1967, Detachment B-43 was deployed to Cao Lanh in Kien Phong Province, with a fully operational airboat facility completed by May. Recognizing the tactical advantage of airboats, the Viet Cong targeted the facility in a devastating mortar and rocket attack on July 3-4, causing significant losses. On June 1, 1967, CAPT Jeffery Fletcher's Thuong Thoi Detachment A-432 was redesignated from A-426. As flooding resumed on September 9, two airboat sections under CAPT Thomas D. Culp and SFC Robert A. Anspach were attached to Fletcher’s command from the Mike Force of A-401 at Don Phuc. Operating from a camp near the Cambodian border close to Hong Ngu, Fletcher became concerned about the deteriorating condition of his main camp berm and the increasing leakage threatening the outpost manned by his 454th CIDG Company along the Mekong River.

On the morning of September 11, 1967, six airboats departed at 0830 hours for a reconnaissance mission. Each boat carried four men, comprising three Special Forces advisors, one interpreter, one LLDB noncommissioned officer, and a mix of Chinese and Cambodian Mike Force soldiers. SFC Robert Anspach led the formation in Boat 1, joined by LLDB SGT Binh, a Chinese soldier, and interpreter Chau Van Sang, who also acted as the driver. CAPT Culp was in Boat 3, while MSGT James W. Lewis occupied Boat 6.

Their mission was to sweep north toward the Cambodian border, then west to the Mekong River. However, due to changes in the landscape caused by the floodwaters, the boats missed their intended turn and entered the river that formed the international boundary. As the first four boats left the stream and entered Vietnamese waters, they were ambushed by Viet Cong bunkers on both sides of the channel. In the initial burst of machine gun fire, all six airboats were heavily damaged, and SFC Anspach was killed instantly. In the ensuing chaos, instead of retreating, the column circled back into the ambush zone, leading to further devastation.

Despite attempts to escape, the boats were overwhelmed. Boat 1, carrying Anspach's body, was later seen being dragged across the border by the Viet Cong. Boat 2 crashed into the riverbank and sank, while CAPT Culp, despite being wounded, was killed in Boat 3 after returning fire. Boats 4 and 5 were either disabled or captured, and MSGT Lewis, wounded in Boat 6, remained in radio contact until he lost consciousness. The entire firefight lasted only two minutes, but its impact was severe: one boat was sunk, two were captured by the enemy, and two were immobilized. Only Boat 3 remained functional.

A rescue mission was quickly launched by SSGT Jackson from A-401 and SFC Pollock from A-432. They managed to recover the surviving soldiers, tow Boat 4 back to camp, and later retrieve Boat 2 with a Chinook helicopter. Airstrikes were called in to destroy Boat 5 and the enemy bunkers. SFC Anspach’s body, however, remained missing. Multiple reports from former Viet Cong and refugee sources indicated that Anspach had either died from his wounds and was buried alone or was buried in a common grave with three others, but all attempts to recover his remains were thwarted by the enemy's presence in the area.

Pictured: Navy Patrol Air Cushion Vehicles (PACV), SFC Robert Allen Anspach