Amphibious aircraft

A Canadair CL-415 amphibian with retractable wheels

An amphibious aircraft, or amphibian, is an aircraft that can take off and land on both land and water. Most amphibious aircraft are fixed-wing, but there are also amphibious helicopters. Fixed-wing amphibious aircraft are seaplanes, such as flying boats and floatplanes, that have retractable wheels. They are heavier and more complex than regular planes and use more fuel.

Design

Floatplanes can sometimes swap floats for wheels, making them a land plane. When this is not possible, amphibious floatplanes, like the amphibious DHC Otter, have wheels built into the floats. Some planes have reinforced keels to land on snow or ice.

Many amphibious planes are flying boats. They may have extra small floats called outrigger floats to stop the wings from tipping into the water. Some planes, like the Catalina, have retractable tip floats. Others, like the Dornier Seastar, use stub wings called sponsons for stability.

Some non-amphibious seaplanes have temporary wheels to move on land, but these cannot take the impact of landing. True amphibians have wheels strong enough to land on both land and water.

Hazards

Pilots must make sure the wheels are in the right position before landing. Landing with wheels up on land can damage the plane, and landing with wheels down on water can flip it over, causing serious damage.

Vickers Viking - an early amphibian.

Usage

Amphibious aircraft are heavier, slower, and more expensive than land planes, but they are more flexible. They can carry out missions over land and water and are often cheaper than helicopters. Amphibians like the Grumman Albatross and Shin Meiwa US-2 are used for air-sea rescue. They are also useful as bush planes in remote areas where lakes and rivers are the only landing spots.

History

In the United Kingdom, amphibious planes were built from 1918 with the Vickers Viking and Seagull for exploration and military use. After World War II, helicopters replaced many amphibians.

In the United States, Sikorsky built many amphibians like the S-38 for exploration and passenger flights. Grumman made the Goose and Widgeon for civilian and military use. The Consolidated Catalina was also adapted as an amphibian in World War II. Later, the Grumman Albatross served the military.

Other countries, like Russia and Italy, also built amphibians. In Russia, the Beriev Be-12 and Beriev Be-200 are examples. Italy made planes like the Piaggio P.136.

Amphibians are still used in Alaska and northern Canada to reach remote areas. Modern examples include the Bombardier 415, ICON A5, and amphibious versions of the Cessna Caravan. Japan developed the ShinMaywa US-2 in the 2000s for rescue missions.

ShinMaywa US-2 amphibious aircraft

Related page

• Unmanned aerial vehicle