them commercial, in Florida alone as of December 2017. Airboats are widely used in other Gulf Coast states, especially Louisiana, but they can be found in rivers, marshes, and icy areas around the world, from Nebraska to Siberia. Soviet airboats and aerosleds Airboats and airboat-like craft have been used in the Soviet Union and its successor states since the Second World War and possibly earlier. Some true airboats—vessels that operated entirely in the water—were used by the Soviet military in World War II. These true airboats include the NKL-5, a WWII armed boat reportedly capable of speeds up to . However, most Soviet airboats are aerosleds (referred to as "aerosanis" in Russian). An aerosled is an aircraft propeller driven amphibious vehicle best described as a hybrid of a sled, airboat, and ground effect vehicle. Thousands of aerosleds were used as cargo and passenger vehicles in Siberia, where they excelled because they could cope equally well with the icy Siberian winter and the muddy, marshy conditions of Rasputitsa season (similar to the American mud season), when raw or thawing snow makes travel by road impossible. Aerosleds are still in use today. The Tupolev A-3 Aerosledge is a quintessential example of this type of vehicle; it can reach speeds of up to 120 kilometers per hour (74.6 mph) on snow and 65 km/h (40.4 mph) on water. History The first airboat was invented in 1905 in Nova Scotia, Canada by Alexander Graham Bell. The earliest airboats to see any kind of use date to 1915, when airboats were used by the British Army in the World War I Mesopotamian Campaign. However, airboats were not widely used by civilians until the 1930s. First prototypes The earliest ancestors of the airboat were waterborne vehicles for testing aircraft engines. The first airboat was the Ugly Duckling, an aircraft propeller testing vehicle built in 1905 in Nova Scotia, Canada by a team led by Dr. Alexander Graham Bell. Ugly Duckling was a catamaran-type boat propelled by an "aerial propeller" hooked up to a water-cooled aircraft engine weighing . The makeshift raft-like vessel was unable to obtain a speed faster than 4 miles per hour (3.5 knots), though the "rapid rotation of the propeller" led Dr. Bell to believe that the vessel could have had a theoretical top speed of "thirty or forty miles an hour," comparable to some modern airboats, if drag was completely eliminated. Brazilian