Amphibious aircraft
Encyclopedia
An amphibious aircraft or amphibian is an aircraft
Aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. An aircraft counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.Although...

 that can take off and land on either land or water. Fixed-wing
Fixed-wing aircraft
A fixed-wing aircraft is an aircraft capable of flight using wings that generate lift due to the vehicle's forward airspeed. Fixed-wing aircraft are distinct from rotary-wing aircraft in which wings rotate about a fixed mast and ornithopters in which lift is generated by flapping wings.A powered...

 amphibious aircraft are seaplanes (flying boat
Flying boat
A flying boat is a fixed-winged seaplane with a hull, allowing it to land on water. It differs from a float plane as it uses a purpose-designed fuselage which can float, granting the aircraft buoyancy. Flying boats may be stabilized by under-wing floats or by wing-like projections from the fuselage...

s and floatplane
Floatplane
A floatplane is a type of seaplane, with slender pontoons mounted under the fuselage; only the floats of a floatplane normally come into contact with water, with the fuselage remaining above water...

s) that are equipped with retractable wheels, at the expense of extra weight and complexity, plus diminished range and fuel economy compared to planes designed for land or water only. Some amphibians are fitted with reinforced keels which act as skiis, allowing them to land on snow or ice with their wheels up and are dubbed Tri-phibians.

Design

While floatplane
Floatplane
A floatplane is a type of seaplane, with slender pontoons mounted under the fuselage; only the floats of a floatplane normally come into contact with water, with the fuselage remaining above water...

s sometimes have floats that are interchangeable with wheeled landing gear (thereby producing a conventional land-based aircraft), it is rare for a floatplane to successfully incorporate retractable wheels whilst retaining its floats; the Grumman J2F Duck would be a notable example of one exception which does. Some amphibian floatplanes, such as the amphibian version of the Cessna Caravan, incorporate retractable wheels within their floats.

The majority of amphibian aircraft are of the flying boat
Flying boat
A flying boat is a fixed-winged seaplane with a hull, allowing it to land on water. It differs from a float plane as it uses a purpose-designed fuselage which can float, granting the aircraft buoyancy. Flying boats may be stabilized by under-wing floats or by wing-like projections from the fuselage...

 type. These aircraft, and those designed as floatplanes with a single main float under the fuselage centerline (such as the J2F Duck), require small outrigger floats to be fitted underneath the wings: while these impose additional drag and weight on all seaplanes of this type, amphibious aircraft also face the possibility that these floats would hit the runway during wheeled landings. A solution would be to have the aircraft fitted with wing-mounted retractable floats such as those found on the Grumman Mallard
Grumman Mallard
|-See also:-References:NotesBibliography* Hotson, Fred W. Grumman Mallard: The Enduring Classic. Scarborough, Ontario: Robin Brass Studio, 2006. ISBN 978-1896941448....

, a flying boat
Flying boat
A flying boat is a fixed-winged seaplane with a hull, allowing it to land on water. It differs from a float plane as it uses a purpose-designed fuselage which can float, granting the aircraft buoyancy. Flying boats may be stabilized by under-wing floats or by wing-like projections from the fuselage...

 type of seaplane designed and built in the mid 1940s
1940s
File:1940s decade montage.png|Above title bar: events which happened during World War II : From left to right: Troops in an LCVP landing craft approaching "Omaha" Beach on "D-Day"; Adolf Hitler visits Paris, soon after the Battle of France; The Holocaust occurred during the war as Nazi Germany...

 with dozens still employed today in regular small volume commercial (ferry service) air taxi roles. The class which has retractable floats which also act as extra fuel tanks since fuel liquids weigh less than water of equal volume; these floats are removable for extended land/snow operations if and when use of extra fuel tanks is undesired but the plane type and class serves as an example of a true amphibious aircraft since they also retract up off the ground.

Usage

Amphibious aircraft are heavier and slower, more complex and more expensive to purchase and operate than comparable landplanes but are also more versatile. Even if they cannot hover or land vertically, for some jobs they compete favorably with helicopters but do so at a significantly lower cost. Amphibious aircraft can be much faster and have longer range than comparable helicopters, and can achieve nearly the range of land based aircraft, as an airplane's wing is more efficient than a helicopter's lifting rotor. This makes an amphibious aircraft, such as the Grumman Albatross
HU-16 Albatross
The Grumman HU-16 Albatross is a large twin-radial engine amphibious flying boat that was utilized by the U.S. Air Force, the U.S. Navy and the U.S. Coast Guard, primarily as a search and rescue and combat search and rescue aircraft...

 and the Shin Meiwa US-1A, ideal for long-range air-sea rescue tasks. In addition, amphibious aircraft are particularly useful as "bush" aircraft engaging in light transport in remote areas, where they are required to operate not only from airstrips, but also from lakes and rivers.

History

Amphibious aircraft have been built in various nations since the early 1920s, but it was not until World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 that saw their widespread service. The Grumman Corporation, a United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

-based pioneer of amphibious aircraft, introduced a family of light utility amphibious aircraft - the Goose
Grumman Goose
The Grumman G-21 Goose amphibious aircraft was designed as an eight-seat "commuter" plane for businessmen in the Long Island area. The Goose was Grumman’s first monoplane to fly, its first twin-engined aircraft, and its first aircraft to enter commercial airline service...

, the Widgeon
Grumman Widgeon
|-See also:-References:NotesBibliography* Donald, David. The Complete Encyclopedia of World Aircraft. New York: Barnes & Noble Books, 1997. ISBN 0-7607-0592-5....

 and the Mallard
Grumman Mallard
|-See also:-References:NotesBibliography* Hotson, Fred W. Grumman Mallard: The Enduring Classic. Scarborough, Ontario: Robin Brass Studio, 2006. ISBN 978-1896941448....

 - during the 1930s and the 1940s, originally intended for civilian market. However, their military potential could not be ignored, and large numbers of these versatile aircraft were ordered by the Military of the United States
Military of the United States
The United States Armed Forces are the military forces of the United States. They consist of the Army, Navy, Marine Corps, Air Force, and Coast Guard.The United States has a strong tradition of civilian control of the military...

 and their allies during World War II, for service in air-sea rescue, anti-submarine patrol, and a host of other tasks. The concept of military amphibious aircraft was so successful that the PBY Catalina
PBY Catalina
The Consolidated PBY Catalina was an American flying boat of the 1930s and 1940s produced by Consolidated Aircraft. It was one of the most widely used multi-role aircraft of World War II. PBYs served with every branch of the United States Armed Forces and in the air forces and navies of many other...

, which began life as a pure flying boat, introduced an amphibian variant during the war.

In the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

, Supermarine Aircraft produced the Walrus
Supermarine Walrus
The Supermarine Walrus was a British single-engine amphibious biplane reconnaissance aircraft designed by R. J. Mitchell and operated by the Fleet Air Arm . It also served with the Royal Air Force , Royal Australian Air Force , Royal Canadian Air Force , Royal New Zealand Navy and Royal New...

 and the Sea Otter
Supermarine Sea Otter
|-Survivors:No museum holds a complete aircraft. Australia's Museum of Flight has the nose section of JN200, a Sea Otter which served with the Royal Australian Navy.-See also:-References:...

 single-engined biplane amphibians which were widely used for observation and air-sea rescue duties before and during World War Two.

After the war, the United States military ordered hundreds of the HU-16 Albatross and its variants for use in open ocean rescue, for the United States Air Force, Coast Guard and Navy.
The capabilities of these amphibious aircraft were found to be particularly useful in the unforgiving terrains of Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

 and northern Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, where some remained in civilian service long after the war, providing remote communities in these regions with vital links to the outside world. Nonetheless, with the increased availability of airstrips and amenities in remote communities, fewer amphibious aircraft are manufactured today than in the past, although a handful of manufacturers around the world still produce amphibious aircraft (flying boats or floatplanes with retractable landing gear), such as the Bombardier 415, the Grumman Albatross and the amphibian version of the Cessna Caravan.

The largest amphibious aircraft currently in service is the Beriev A-40
Beriev A-40
This article is about the amphibious jet. For Soviet tank airlift project, see Antonov A-40.This article is about the amphibious jet. For Soviet tank airlift project, see Antonov A-40.This article is about the amphibious jet...

 of the Russian Navy, with a wingspan of 41.62 meter and a takeoff weight of 86 metric tons. The Beriev Be-200
Beriev Be-200
The Beriev Be-200 Altair is a multipurpose amphibious aircraft designed by the Beriev Aircraft Company and manufactured by Irkut. Marketed as being designed for fire fighting, search and rescue, maritime patrol, cargo, and passenger transportation, it has a capacity of 12 tonnes of water, or up...

 is a smaller model for civil applications and had its first flight in 2004. It can carry 72 passengers and is also built in a version for fire fight.

See also

  • Amphibious helicopter
    Amphibious helicopter
    An amphibious helicopter is a helicopter that is intended to rest and take off from either land or 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...

  • Beriev
  • List of seaplanes and flying boats
  • Seaplane
    Seaplane
    A seaplane is a fixed-wing aircraft capable of taking off and landing on water. Seaplanes that can also take off and land on airfields are a subclass called amphibian aircraft...

  • Floatplane
    Floatplane
    A floatplane is a type of seaplane, with slender pontoons mounted under the fuselage; only the floats of a floatplane normally come into contact with water, with the fuselage remaining above water...

  • Flying boat
    Flying boat
    A flying boat is a fixed-winged seaplane with a hull, allowing it to land on water. It differs from a float plane as it uses a purpose-designed fuselage which can float, granting the aircraft buoyancy. Flying boats may be stabilized by under-wing floats or by wing-like projections from the fuselage...

  • RAPT system
    RAPT system
    Tigerfish Aviation is an aerospace research and development company based in Norwood, South Australia. Since the late 1990s, the company has been developing a retractable pontoon system for the float plane industry, which has been patented as Retractable Amphibious Pontoon Technology or RAPT.-RAPT...

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