because it was found to be effective only for suppressive fire. The Army ACVs had other improvements over the Navy PACVs beyond their additional armor, namely a wider cockpit, more horsepower, two gun positions instead of one, and a flat deck on top of the skirt for troops to ride on. Operational history PACVs were first deployed to Vietnam in May 1966 as PACV Division 107, Task Force 116, where they were used by the Navy for riverine patrol missions in the Mekong Delta and on the Mekong River. Often called "Pac Vees", they were armed with a .50 caliber machine gun mounted on a rotating platform in the front and two side-mounted M60 machine guns. In addition, the crew, and often US Army Special Forces and ARVN Rangers, riding on the side panels, employed assorted small arms such as M16 rifles and M79 grenade launchers as well as various other rifles, .45 pistols, light and medium machine guns, and grenades, although using small arms was dangerous because spent casings could fall into the propeller. The PACV was used to prevent Viet Cong infiltration from the sea and tidal areas along river mouths and deltas. It was especially useful in shallow marshy areas, especially the Mekong Delta, where other patrol boats such as the Patrol Boat, River or Patrol Craft Fast (Swift boat) could not go. The PACV's relatively light weight of only seven tonnes meant that it could be easily carried by a CH-54 helicopter. This allowed it to be airlifted between forward operating bases or transported back to base when it suffered damage. The PACV could also be split into sections and then transported in Air Force transport planes, which was how they were brought to Vietnam. 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