Navy PACVs were deployed in Operations Game Warden and Market Time, the Navy's operations to deny Viet Cong access to resources in the Mekong Delta and prevent North Vietnamese weapons, fighters, and supplies from entering South Vietnam, respectively. The PACVs were deemed unsuitable for Operation Game Warden because of their "mechanical unreliability" and the limitations imposed on them by terrain. As a result, they were removed from the operation and transferred to another Navy unit, CTF 117. They were also found unsuitable for Market Time operations after serving in that operation from 20 September to 17 October 1966, due to their high noise, low visibility, high cost, and limited utility on the high seas or in narrow waterways. In November 1966, the Navy PACVs were used to great effect in Operation Quai Vat (Vietnamese for "Monster", which was what the Viet Cong called the PACVs). In the operation on the Plain of Reeds, conducted jointly with Vietnamese Civilian Irregular Defense Group (CIDG) troops and Army helicopters and special forces, the PACV force brought its speed and firepower to bear on the Viet Cong, killing at least 23 of them, destroying 70 of their sampans and an equal number of their structures, taking many prisoners, and capturing their supplies. This demonstration of combat prowess in the marshy terrain in southwestern Vietnam formed the basis for stationing the Army ACVs in the Plain of Reeds along the South Vietnamese/Cambodian border. An Army evaluation found that in the Plain of Reeds, "any mission requiring ground operations can best be accomplished by ACV unts," particularly reconnaissance, light assaults, infantry transport, canal security, cordoning off areas to prevent escape, and patrolling. Though the loud noise of the PACVs was an issue, their speed made up for it in this otherwise difficult terrain, especially during the monsoon season. The PACV could clear rice paddy dikes and other solid obstacles up to high and negotiate slopes of up to . However, the PACV did not perform well in the dry season, with an Army evaluation noting that "The wetter the season, the better for vehicle operations".