Вьетнам соғысында қолданылған американдық әуе кемесі (PACV)

Hovercraft

Name=PACVBuilders=British Hovercraft Corporation, Bell AerosystemsOperators=*US Navy
US Army
US Coast GuardClass before=Class after=Subclasses=Cost=$1 millionBuilt range=1965In service range=In commission range=1966–1970Total ships building=Total ships planned=Total ships completed=6Total ships cancelled=Total ships active=Total ships laid up=Total ships lost=3

The Patrol Air Cushion Vehicle (PACV), also known as the Air Cushion Vehicle (ACV) in Army and Coast Guard service, was a United States Navy and Army hovercraft used as a patrol boat in marshy and riverine areas during the Vietnam War between 1966 and 1970. Six hovercraft were built, three for the Army and three for the Navy. The military developed the PACV because its lack of draft meant that it could operate unimpeded in the shallow and reed choked waters widespread in South Vietnam, most notably in the Mekong Delta and Plain of Reeds. Following their service in Vietnam, the Navy PACVs returned to the United States where they were used by the Coast Guard, Design of the Army ACVs began in 1966 and was completed

Two different designs were made: one for the Navy and one for the Army. The Navy's hovercraft, called Patrol Air Cushion Vehicles, more closely resembled the civilian SK 5s that they were based on while the Army craft had more extensive modifications. Each hovercraft was 38 feet (12 m) long, Army and Navy PACVs had a crew of 4—driver, radar operator, and gunners—and could carry up to 12 troops, many of whom rode on the outside of the vehicle. Both designs were powered by a General Electric 7LM100 PJ102 gas turbine engine. The transmission served to link the engine and lift fan so that the fan could provide lift and thrust. Twin rudders and elevators sat behind the fans. As a hovercraft, the PACV could skim over water, including shallow and reed choked waters, flat land, and ice. To save weight, many crews removed the armor around the crew compartment, especially against heavier weapons such as recoilless rifles, artillery, and RPGs. The communications package consisted of a six station intercom system, UHF radios, and a radio security set. The boats were shipped with AN/ARC 54 FM radios. However, these proved unreliable, with an operational ready rate of only 35 percent. Army units sought to replace them with VRC 125s. While it is not known if this replacement occurred, one ACV did receive a VRC 46 radio. because it was found to be effective only for suppressive fire. 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. The PACVs were deemed unsuitable for Operation Game Warden because of their "mechanical unreliability" and the limitations imposed on them by terrain. 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, and capturing their supplies. Also in 1968, the Army began employing its version of the PACV, the ACV. The Army acquired the vehicles and activated their unit, the 39th Cavalry Platoon, in January before deploying them to Vietnam in April. There were only three Navy PACVs and three Army ACVs during the whole Vietnam War. Two of the three ACVs (No. 901 and 902) were Assault Air Cushion Vehicles (AACV), weapons heavy vessels configured for attack missions, while the other (No. 903) was a Transport Air Cushion Vehicle (TACV) configured for logistics missions. The TACV only carried the twin M60s, forgoing the .50 cal and other weapons to increase space in the cabin for carrying troops. Both AACVs were lost to Viet Cong attacks. The three Army ACVs were operated by the 39th Cavalry Platoon, 9th Division, and were based out of Ben Luc and Đồng Tâm Base Camp,

The Green Berets stationed in Moc Hoa became proponents of the PACVs, using them in many of their early operations. Search and destroy raids conducted out of Moc Hoa in November 1966 caught the Viet Cong by surprise and resulted in many Viet Cong deaths. Although it was too loud to be very effective at surprise attacks, it could use its speed to raid Viet Cong bases and escape before they could react. The PACV was found to be most effective when employed in combined arms operations alongside helicopters, artillery, and other watercraft; patrol missions conducted in concert with air cavalry or Hurricane Aircat airboats were found to be especially effective. The PACV's low profile and radar also meant that it was used as a stealthy stationary radar station when its engines were off. However, Army evaluations found that the ACV had insufficient firepower, being unable to damage armored or fortified targets, and recommended that it be outfitted with heavier weapons such as TOW missiles, 20mm autocannons (such as the M139 or M61 Vulcan), or 106mm M40 recoilless rifle. They also found that it could be too loud to be used effectively for patrol and interdiction missions. Another downside of the PACV was the degree of maintenance it required: each hour of operation required 20 hours of maintenance,refn|group=lower alpha|A 1968 Army evaluation gives a lower figure of 2.1 hours of maintenance per hour of operation, although it also cites the PACV's maintenance requirements as a major downside. combined with the insufficient firepower to lead an Army evaluation to conclude that "there is no hope of the [PACV/ACV] unit fighting to a satisfactory conclusion in any large engagement." as much as 13 Patrol Boat, Rivers. refn|group=lower alpha|The Patrol Boat, River cost $75,000 ($593,000 in 2018 dollars).

Following their withdrawal in 1970, the Navy PACVs were transferred to the U. S. Coast Guard for evaluation. and the third was used for Arctic Trials in Point Barrow, Alaska, The Coast Guard PACVs were modified to meet their requirements by replacing the .50 cal gun mount with an observation dome and adding a KAAR LN66 radar and search and rescue equipment. The San Francisco ACVs were evaluated for use as a crash/fire rescue vehicle at Oakland International Airport in 1972 and were found to be successful. One of the San Francisco based ACVs was showcased by the Coast Guard at the U. S. International Transportation Exposition at Dulles International Airport in 1972, where it was inspected by tens of thousands of international visitors. Over the first two years of evaluation, the Coast Guard ACVs accrued over 1,500 hours of operating time. After this sinking, one of the two San Francisco ACVs was then transferred to the Great Lakes. As such, the two surviving ACVs were transferred to US Army Mobility Equipment Research and Development Center in Fort Belvoir, Virginia, on 25 April 1975.

The sole surviving Army ACV (No. 903) was transferred to the U. S. Army Transportation Museum in Fort Eustis, Virginia, where it is still on display
The only surviving US Navy PACV (No. 004) is preserved at the Yanks Air Museum in Chino, California.