Airboats are flat-bottomed vessels propelled by a large aircraft-style propeller mounted above the stern and driven by an automotive or aviation engine. Because the propulsion system is entirely above the waterline, airboats can operate in extremely shallow water — often just a few centimetres of depth — as well as over mud, marsh vegetation, and ice, where submerged propulsion systems would be inoperable.
Hulls are typically fabricated from aluminium or fibreglass. Draft is minimal: a loaded airboat may draw 10–15 centimetres. Steering is achieved by rudders mounted in the propeller airstream rather than water rudders, which means the boat cannot manoeuvre when the engine is off. Noise levels are high — ear protection is standard on commercial operations — and the open seating arrangement provides no shelter from wind or spray. Airboats are not suitable for open water or significant wave conditions.
The type was developed for access in the Florida Everglades and similar environments and remains in working use for rescue, law enforcement, and environmental survey operations in wetland areas across North America, Southeast Asia, and elsewhere. Recreational use — primarily fishing and eco-tourism — accounts for much of the civilian market. Engine outputs typically range from 150 to over 500 horsepower; larger units can reach speeds above 80 km/h in suitable conditions. Regulatory restrictions apply on noise-sensitive waterways in several jurisdictions.
