hulls while airboats intended for use in marshes will have lighter fiberglass hulls, for instance. Standard hunt/trail boats are long with a two- to three-passenger capacity. Tour boats can be much larger, accommodating 18 passengers or more. Engines are either an air-cooled, 4- or 6-cylinder aircraft or water-cooled, large-displacement, V8 automotive engine, ranging from 50 to over 600 hp. Automotive engines tend to be less expensive due to readily-available replacement parts and less expensive high octane automotive gas. Since an opposed, 4- or 6-cylinder (O4 or O6) aircraft powerplant contains fewer moving parts than a standard automotive engine, it is easier to repair and weighs less. However, automotive engines can be repaired by more-common car mechanics and do not require specialized repair personnel like aircraft engines do. Most of the sound produced by an airboat comes from the propeller, although the engine itself also contributes some noise. Modern airboat designs are significantly quieter thanks to mufflers and multi-blade carbon-fiber propellers. Safety As with any vehicle, the safety of an airboat is dependent on the training and skill of its operator and the use of safety features like seat belts and flotation devices/life jackets. Airboats should only be piloted by trained and qualified operators, and knowledge of operational safety is essential when operating an airboat. Over 75 airboat accidents happened in Florida between 2014 and 2017, resulting in seven deaths and 102 severe injuries. Most (five of seven) deaths were drownings, and 90 percent of accident victims were not wearing life jackets, even though only 30 percent knew how to swim. Not wearing a seat belt is another major predictor of injury in an accident: 40 percent of injured victims and the only two non-drowning fatalities were flung from their seats in the crashes. The most common injuries suffered in airboat accidents are severe cuts, bruises, and broken limbs. Other severe injuries are not uncommon: 10 percent of injured people suffered neck and back injuries requiring surgery and long-term pain medication and another 10 percent suffered traumatic head and brain injuries. Most airboat accidents—64%—are the fault of the operator, according to a 2017 analysis by the Miami New Times, almost always due to one of three factors: a lack of boating education or training; a lack of safety equipment, such as seat belts or flotation devices, or a failure to properly use safety equipment; or reckless behavior, including drug or alcohol