In 1959 this chap by the name of Christopher Cockerell working for Saunders-Roe on the Isle of Wight came up with the first working and practical hovercraft, the “Saunders-Roe Nautical 1” (SR.N1), using an Alvis Leonides radial piston engine that drove a lift fan, and used ducted air from the fan for propulsion, producing a neat three-person craft that was capable of crossing the Channel at 35 knots.
This led to the 65-foot SR.N2 in 1961, which could make 73 knots (that’s seventy-three) and carry 48 passengers.
1963 brought the SR.N3 which was designed for military use and mounted a quartet of Bristol-Siddeley Gnome gas turbines, which enabled it to make 70 knots. The prototype didn’t work out too well but set the stage for what was to come.
SR. N3 Loading Royal Marines at Cowes for the Inter-Service Hovercraft Unit trials.
Saunders-Roe and Vickers Supermarine merged to become the British Hovercraft Corporation (BHC) in 1966, and their fourth hovercraft, SR.N4, was a mammoth design that eventually topped out at 185-feet long. While the RN theorized using these as mine countermeasures craft, these vessels, of which six were eventually built, were used as passenger ferries as last as 2000.
Then came the primary subject of our tale, the SR.N5 military model of which 14 were built, half by BHC in the UK and the other half Bell in the U.S..
Navy patrol air cushion vehicle glides over the waters of Cau Hai Bay near Hue, South Vietnam hovercraft
These 39-foot hovercraft were beamy, at 22 feet wide, and tall at almost 17 feet with the skirt inflated. Powered by a single 900hp Rolls-Royce Gnome turbine for both lift and propulsion, they could make 70 knots and carried enough jet fuel for about 3-4 hours of patrol. They could carry 16 troops.
The hovercraft were flown more than they were sailed
Of the 7 British built vessels, one each were bought by the Sultanate of Brunei and the Canadian Coast Guard, the Brits kept four for the RNAS and the last UK boat went into commercial use. Of the 7 Bell hovercraft (designated SK-5s by that company and equipped with a GE engine), three were bought by the U.S. Navy as Patrol Air Cushion Vehicle (PACV, “Pac Vees”) and three by the U.S Army as Air-Cushion Vehicles (ACV) while the last U.S. boat was bought by San Francisco and Oakland Helicopter Airlines to use as a high speed ferry around the Bay Area.
Navy PACV, dig the mouth
In U.S. military service in Vietnam, these hovercraft picked up .50 cal and 7.62mm machine guns, a modicum of armor and sandbags to protect their four-man crews (thought they could get by with just two crewmen), and by 1966 were hot and heavy in South East Asia as part of Task Force 116 for the Navy craft while the Army’s boats followed the next year as the catchy Air Cushion Vehicle Test Unit, (Armor Platoon Air Cushioned) 39th Cavalry Platoon of 24 men.
Navy PACV3. Note the sandbagged fighting position atop the house
Operating on the Mekong Delta, Cat Lo, and other hot spots, these half-dozen craft were soon dubbed Quai Vat (Monsters) by Mr. Charles as they raced around the swamps dropping off ARVN troops, Nung mercenaries and U.S. forces in hard-to-reach mudbogs. They were loud as hell (ever been around an LCAC?) but they were effective and, with the turbine shut down and the skirt on a relatively dry spot in the middle of the marsh, they were instant fighting positions.
By early 1968, the Army was even looking at (neat report here) making entire platoons of these craft, armed with 106mm recoilless rifles, Tow or Shillelagh missiles and FFAR rockets much like the helicopter gunships of the day.
Army ACV
Army ACV. They weren’t as wild as the Navy’s PACVs
That Loach is really hugging (and looks like it is having a hard time keeping up)
Then came the epic six-day battle in the Plain of Reeds.
While conducting a combat operation in July 1968 in support of a South Vietnamese CIDG (Civilian Irregular Defense Force) unit and US infantry advisors, the Army SK5s were engaged in a 7-hour continuous fight with enemy forces.
During the reconnaissance sweep, the SK5 boats inspected over 60 houses along the waterline and discovered over 25 bunkers within the area.
After destroying the bunkers with their supporting infantry, the two hovercraft came under enemy fire. Both craft returned fire, but were unable to press the attack since the CIDG forces were unwilling to dismount into a potential ambush.
After disengaging, both ACVs repositioned to another area and were once again taken under fire. Both vessels returned fire and when the infantry inspected the area they discovered several killed enemy soldiers.
All was good until one of the Army craft, ACV #901, was destroyed on 9 Jan 1970. ACV #902 was destroyed in August 1970. The final Army unit, #903 was returned stateside.
The three Navy PACVs were likewise brought back CONUS and transferred to the Coast Guard in 1971.
Behold, the Coast Guard’s hovercraft fleet!
They actually look snazzy in hi-viz livery. Above is CG-38102, formerly PACV1.
Numbered CG-38101, 38102 and 38103, one (103) was lost in an accident while the first two were transferred to the US Army Mobility Equipment Research and Development Center on 25 April 1975, making the Army the only U.S. military hovercraft owner until the Navy took possession of the first 87-foot long Landing Craft Air Cushion (LCAC) vessels in 1986.
Of the British hovercraft, the original SR.N1 is held by the Science Museum at Wroughton, the only SR.N2 was broken up in the 1970s, SR.N3 was used for target practice, 4 of the 6 SR.N4 ferries were broken up and the two left are currently at the Hovercraft Museum in Lee-on-the-Solent but are facing imminent destruction.
Of the SR.N5s, one U.S Army boat, ACV 903, was returned to the states and is on display at the Transportation Museum in Ft. Eustis, VA. The sole remaining Navy PACV is at the Bellingham International Maritime Museum in Washington.
As for the British Hovercraft Corporation, moving past the SR.N5s they built the 58-foot SR.N6 in large numbers in the 1960s, being their most successful model of all with at least 54 completed. Popular in commercial use as a 58-passenger ferry, a military version capable of carrying a platoon was used by the Canadian Coast Guard, Italian Navy, Egyptian Navy, Iraqi Navy, Iranian Navy and the Saudi Arabian Frontier Force. The Shah liked them so much he ordered a half dozen larger 78-foot BH.7 hovercraft in the early 1970s while the CCG bought three of BHC’s last hovercraft, the 90 passenger AP1-88 boats before the company folded in 1984.
But we do have 91 U.S.-built LCACs today…
A landing craft air cushion leaves the well deck aboard the USS Iwo Jima in the Persian Gulf, Sept. 21, 2006
