An amphibious helicopter is a helicopter that is intended to land on and take off from both land and water. Amphibious helicopters are used for a variety of specialized purposes including air-sea rescue, marine salvage and oceanography, in addition to other tasks that can be accomplished with any non-amphibious helicopter. An amphibious helicopter can be designed with a waterproof or water-resistant hull like a flying boat or it can be fitted with utility floats in the same manner as a floatplane.[1]
Helicopters have taken a primary role in air-sea rescue since their introduction in the 1940s.[2] Helicopters can fly in rougher weather than fixed-wing aircraft, and they can deliver injured passengers directly to hospitals or other emergency facilities. A practical amphibious helicopter first appeared in 1941[3] and the water-landing feature soon proved its worth. Non-amphibious helicopters were required to hover above the scene of a water accident and utilize a hoist but amphibious helicopters were capable of setting down on the water to effect a rescue more directly.[4]
Fitted floats
In 1941, Igor Sikorsky fitted utility floats (also called pontoons) to the Vought-Sikorsky VS-300, making the first practical amphibious helicopter.[3][5] In the 1940s and 1950s, some models of helicopter such as the Bell 47 and 48 and the Sikorsky R-4 and R-6[6] were fitted with utility floats so that they could rest on both water and land.[7]
Pontoons can be filled with air or they can be utilized for storage of fuel or supplies. In 1949, Sikorsky produced the H-5H with both wheels and pontoons.[8]
The Sikorsky S-62 Seaguard was the first amphibious helicopter made with a flying boat hull—the prototype flew in 1958.[9] Utilizing many components of the earlier S-55, the S-62 proved the idea, and Sikorsky flew their S-61 Sea King prototype in 1959 for the U.S. Navy, a model intended for anti-submarine warfare.[10] Both the S-62 and S-61 were ready for delivery in 1961. Sikorsky produced 1100 S-61s, including some that were not watertight: a longer cargo-carrying version was given rear doors and a ramp. Sikorsky licensed other manufacturers such as Agusta, Mitsubishi and Westland to produce variants of the S-61.[11]
Amphibious helicopters came into their own in the 1960s when robust boat-hulled designs were produced in quantity for military and civilian operators. Amphibious helicopters paid dividends for rescue personnel who enjoyed greater safety and success during operations.[4] Overwater operations that used non-amphibious helicopters relied to a higher degree on hoists, rescue baskets, and rescue swimmers.[4] Nevertheless, beginning in the 1970s, amphibious models were steadily replaced by helicopter models unable to land on water, because of high amphibious aircraft development costs.[4] The last amphibious helicopter model used by the United States Coast Guard was the Sikorsky HH-3F Pelican, retired in 1994.[12]
Resting on the surface of the water with the rotor stopped, in conditions of brisk wind and mounting surface waves, a boat-hulled helicopter with stabilizing floats on either side is less likely to remain upright than a non-boat helicopter fitted with utility pontoons.[13] Difficulty in lifting off can be encountered, especially when heavily loaded or in increasing seas.
The Canadian Forces developed a technique called water bird for landing their CH-124 Sea Kings in water.
Limited water capability
Helicopters can be designed to withstand limited contact with the surface of a body of water. The 1958 Vertol HUP-2 was an amphibious development of the twin-rotor Piasecki H-25 which strengthened its hull and replaced lower nose windows with tough aluminum.[14] The HUP-2 was provided with a pair of stabilizing outrigger floats positioned amidships. The HUP-2 was able to taxi forward or backward on water, regardless of wind direction.[15]
The CH-46 Sea Knight and its Canadian variant, the CH-113 Labrador, can land on water and rest for up to two hours[16] in calm water.[17] The rear sponsons hold two of the three landing gear units as well as self-sealing fuel tanks. The helicopter began service with the United States Marine Corps in 1962,[16] and with the Canadian military in 1963, and is used to carry cargo and combat troops.
A Sikorsky Sea King with an added inflatable emergency float outboard of the standard sponson, intended to increase flotation time
The Boeing CH-47 Chinook was made sufficiently watertight to allow it to land on water for a short time in carrying out covert operations and special military missions. Buoyancy was increased with sealed compartments inside sponsons which extended most of the way along each side of the fuselage. For extended water usage, Boeing offered a kit to enhance its water resistance.[18] The Sikorsky CH-53 Sea Stallion, first introduced in 1966, is also capable of limited water landing.
^US Army TACOM-R1. Historic Army Helicopters: World War II thru early Vietnam era helicopters (Page 1 of 3). March 25, 2009, at the Wayback Machine Retrieved on September 22, 2009.
^Bell, Ryan Corbett. The Ambulance: A History, p. 168. McFarland, 2008. ISBN0-7864-3811-8
^Fitzsimons, Bernard, general editor. Illustrated Encyclopedia of 20th Century Weapons and Warfare (London: Phoebus, 1978), Volume 20, p.2173, "R-5, Sikorsky".
^Popular Mechanics, April 1958, p. 101. "Amphibious Helicopter Rides Outrigger Floats." Retrieved on September 22, 2009.
^ abNational Geographic. On Board Marine One: Facts. September 6, 2009, at the Wayback Machine Retrieved on September 28, 2009.
^Air Vectors. The Boeing Sea Knight & Chinook. "Sea Knight In Military Service." October 3, 2009, at the Wayback Machine Retrieved on September 28, 2009.
^Boeing. Image Gallery. CH-47SD. December 13, 2009, at the Wayback Machine CH-47D/F. 2012-10-10 at the Wayback Machine Retrieved on September 22, 2009.
^Brent, P.T. (February 2009). . Leatherneck Magazine. Archived from the original on 2009-10-11. Retrieved September 22, 2009.
Bibliography
Evans, Clayton. Rescue at sea: an international history of lifesaving, coastal rescue craft and organisations. Naval Institute Press, 2003. ISBN1-59114-713-1
McGowan, Stanley S. Helicopters: an illustrated history of their impact. ABC-CLIO, 2005. ISBN1-85109-468-7
Ostrom, Thomas P. The United States Coast Guard, 1790 to the present: a history. Elderberry Press, Inc., 2004. ISBN1-932762-15-9
Patillo, Donald M. Pushing the Envelope: The American Aircraft Industry. University of Michigan Press, 2001. ISBN0-472-08671-5
External links
Popular Mechanics, October 1949. "Amphibious Helicopter Has Wheels and Floats"
August 20, 2023
amphibious, helicopter, amphibious, helicopter, helicopter, that, intended, land, take, from, both, land, water, used, variety, specialized, purposes, including, rescue, marine, salvage, oceanography, addition, other, tasks, that, accomplished, with, amphibiou. An amphibious helicopter is a helicopter that is intended to land on and take off from both land and water Amphibious helicopters are used for a variety of specialized purposes including air sea rescue marine salvage and oceanography in addition to other tasks that can be accomplished with any non amphibious helicopter An amphibious helicopter can be designed with a waterproof or water resistant hull like a flying boat or it can be fitted with utility floats in the same manner as a floatplane 1 An HH 3F Pelican helicopter of the United States Coast Guard lands on the water near a burning boat Contents 1 Development 2 Fitted floats 3 Boat hull design 4 Limited water capability 5 Roles 6 Examples 7 See also 8 References 9 External linksDevelopment EditHelicopters have taken a primary role in air sea rescue since their introduction in the 1940s 2 Helicopters can fly in rougher weather than fixed wing aircraft and they can deliver injured passengers directly to hospitals or other emergency facilities A practical amphibious helicopter first appeared in 1941 3 and the water landing feature soon proved its worth Non amphibious helicopters were required to hover above the scene of a water accident and utilize a hoist but amphibious helicopters were capable of setting down on the water to effect a rescue more directly 4 Fitted floats EditIn 1941 Igor Sikorsky fitted utility floats also called pontoons to the Vought Sikorsky VS 300 making the first practical amphibious helicopter 3 5 In the 1940s and 1950s some models of helicopter such as the Bell 47 and 48 and the Sikorsky R 4 and R 6 6 were fitted with utility floats so that they could rest on both water and land 7 Pontoons can be filled with air or they can be utilized for storage of fuel or supplies In 1949 Sikorsky produced the H 5H with both wheels and pontoons 8 Boat hull design Edit A Canadian Forces CH 124 Sea King shows its boat hull sponsons and wheeled landing gear The Sikorsky S 62 Seaguard was the first amphibious helicopter made with a flying boat hull the prototype flew in 1958 9 Utilizing many components of the earlier S 55 the S 62 proved the idea and Sikorsky flew their S 61 Sea King prototype in 1959 for the U S Navy a model intended for anti submarine warfare 10 Both the S 62 and S 61 were ready for delivery in 1961 Sikorsky produced 1100 S 61s including some that were not watertight a longer cargo carrying version was given rear doors and a ramp Sikorsky licensed other manufacturers such as Agusta Mitsubishi and Westland to produce variants of the S 61 11 Amphibious helicopters came into their own in the 1960s when robust boat hulled designs were produced in quantity for military and civilian operators Amphibious helicopters paid dividends for rescue personnel who enjoyed greater safety and success during operations 4 Overwater operations that used non amphibious helicopters relied to a higher degree on hoists rescue baskets and rescue swimmers 4 Nevertheless beginning in the 1970s amphibious models were steadily replaced by helicopter models unable to land on water because of high amphibious aircraft development costs 4 The last amphibious helicopter model used by the United States Coast Guard was the Sikorsky HH 3F Pelican retired in 1994 12 Resting on the surface of the water with the rotor stopped in conditions of brisk wind and mounting surface waves a boat hulled helicopter with stabilizing floats on either side is less likely to remain upright than a non boat helicopter fitted with utility pontoons 13 Difficulty in lifting off can be encountered especially when heavily loaded or in increasing seas The Canadian Forces developed a technique called water bird for landing their CH 124 Sea Kings in water Limited water capability EditHelicopters can be designed to withstand limited contact with the surface of a body of water The 1958 Vertol HUP 2 was an amphibious development of the twin rotor Piasecki H 25 which strengthened its hull and replaced lower nose windows with tough aluminum 14 The HUP 2 was provided with a pair of stabilizing outrigger floats positioned amidships The HUP 2 was able to taxi forward or backward on water regardless of wind direction 15 A Vertol HUP Retriever lands on waterThe CH 46 Sea Knight and its Canadian variant the CH 113 Labrador can land on water and rest for up to two hours 16 in calm water 17 The rear sponsons hold two of the three landing gear units as well as self sealing fuel tanks The helicopter began service with the United States Marine Corps in 1962 16 and with the Canadian military in 1963 and is used to carry cargo and combat troops A Sikorsky Sea King with an added inflatable emergency float outboard of the standard sponson intended to increase flotation timeThe Boeing CH 47 Chinook was made sufficiently watertight to allow it to land on water for a short time in carrying out covert operations and special military missions Buoyancy was increased with sealed compartments inside sponsons which extended most of the way along each side of the fuselage For extended water usage Boeing offered a kit to enhance its water resistance 18 The Sikorsky CH 53 Sea Stallion first introduced in 1966 is also capable of limited water landing Roles EditAmphibious helicopters have been used in a variety of roles including air sea rescue anti submarine warfare supporting special forces operations and transporting the US president 19 Examples Edit A Polish Mil Mi 14Boat hulledAerospatiale Super Frelon Changhe Aircraft Industry Group Changhe Z 8 Z 8A Z 8F and Z 8AEW Chinese built variant of Super Frelon Mil Mi 14 Haze Sikorsky S 62 HH 52A Seaguard Sikorsky SH 3 Sea King Sikorsky S 61 Sikorsky CH 124 Sea King Canadian built version of S 61 Sikorsky HH 3F Pelican Westland Sea KingSee also EditAmphibious aircraft Amphibious vehicleReferences EditNotes McGowan 2005 pp 68 84 160 Evans 2003 p 264 a b Sikorsky com Timeline Archived November 3 2009 at the Wayback Machine Retrieved on September 22 2009 a b c d Ostrom 2004 p 186 McGowan 2005 p 27 US Army TACOM R1 Historic Army Helicopters World War II thru early Vietnam era helicopters Page 1 of 3 Archived March 25 2009 at the Wayback Machine Retrieved on September 22 2009 Bell Ryan Corbett The Ambulance A History p 168 McFarland 2008 ISBN 0 7864 3811 8 Fitzsimons Bernard general editor Illustrated Encyclopedia of 20th Century Weapons and Warfare London Phoebus 1978 Volume 20 p 2173 R 5 Sikorsky Patillo 2001 p 209 McGowan 2005 p 118 McGowan 2005 p 119 Lurch Bruno United States Coast Guard Coughlan Publishing 2003 p 17 ISBN 1 4034 4556 7 The Aeronautical Journal Volume 73 1969 p 708 Royal Aeronautical Society McGowan 2005 p 62 Popular Mechanics April 1958 p 101 Amphibious Helicopter Rides Outrigger Floats Retrieved on September 22 2009 a b National Geographic On Board Marine One Facts Archived September 6 2009 at the Wayback Machine Retrieved on September 28 2009 Air Vectors The Boeing Sea Knight amp Chinook Sea Knight In Military Service Archived October 3 2009 at the Wayback Machine Retrieved on September 28 2009 Boeing Image Gallery CH 47SD Archived December 13 2009 at the Wayback MachineCH 47D F Archived 2012 10 10 at the Wayback Machine Retrieved on September 22 2009 Brent P T February 2009 Marine One Welcome aboard Leatherneck Magazine Archived from the original on 2009 10 11 Retrieved September 22 2009 BibliographyEvans Clayton Rescue at sea an international history of lifesaving coastal rescue craft and organisations Naval Institute Press 2003 ISBN 1 59114 713 1 McGowan Stanley S Helicopters an illustrated history of their impact ABC CLIO 2005 ISBN 1 85109 468 7 Ostrom Thomas P The United States Coast Guard 1790 to the present a history Elderberry Press Inc 2004 ISBN 1 932762 15 9 Patillo Donald M Pushing the Envelope The American Aircraft Industry University of Michigan Press 2001 ISBN 0 472 08671 5External links EditPopular Mechanics October 1949 Amphibious Helicopter Has Wheels and Floats Retrieved from https en wikipedia org w index php title Amphibious helicopter amp oldid 1038332362, wikipedia, wiki, book, books, library,
