An amphibious aircraft is an aircraft that can routinely both by water and by land operate. This is achieved by the use of floats or hulls for underwater use, combined with a retractable landing gear for use on land. Frequently amphibious aircraft, the wheels may extend also in the water and then roll on a slipway on land.
The world 's largest amphibian is the Russian Beriev Be - 42, which flew for the first time in 1986. It has a wingspan of 42 meters and reaches with two jet engines, a top speed of 760 km / h