GA is composed of a diverse fleet of aircraft, including airplanes, gliders, and helicopters, that are flown for a variety of purposes (see fig. 1). In 2013, FAA estimated there were about 340,000 licensed GA pilots, and approximately 200,000 aircraft were in the active GA fleet, with airplanes comprising the vast majority—almost 79 percent. According to FAA 2013 data, most GA airplanes are light, single-engine piston, fixed-wing aircraft. FAA also identifies a small, but growing portion of the GA fleet as “experimental” aircraft, which include amateur and home-built aircraft and aircraft used for racing and research (among other purposes), as well as exhibition aircraft, such as former military aircraft that are commonly referred to as “warbirds.” The majority of these GA aircraft (about 88 percent) are used for one of the following purposes: personal (e.g., a pilot taking a family on a sightseeing trip); business (e.g., an owner and pilot flying to a meeting); corporate (e.g., a professionally-piloted aircraft transporting corporate employees); and instructional (e.g., a student flying with a certified flight instructor). Domestic GA operations are conducted from more than 2,950 public-use GA airports (which primarily serve GA aircraft) as well as from thousands of other airports, including those that support commercial air service. GA flights operate under various federal aviation regulations. For the purposes of this report, our definition of GA includes flights operated under Part 91 of general operations and flight rules, namely, all civilian aviation flying except passenger air carriers and military aircraft. Although the number of GA accidents in the United States has been generally decreasing in recent years, there were over 1,200 accidents and over 400 resulting fatalities in 2014 (see table 1). In October 2012, we found that most GA accidents involved personal use and instructional flight operations. In 2014, personal use and instructional flight operations combined accounted for about 75 percent of GA accidents. Most accidents also occurred during the landing and take-off phases of a flight, and in 2014 most GA accidents occurred in California, Texas, and Florida, all states with large numbers of GA aircraft. Two federal agencies are primarily responsible for investigating GA accidents and ensuring aviation safety: FAA and NTSB. FAA is responsible for administering aircraft registration and pilot certification, conducting safety oversight of pilots’ training and GA operations, and taking enforcement actions against pilots and others who violate federal aviation regulations and safety standards. FAA also collects GA fleet and flight activity data through an annual survey that includes the number of hours flown and the uses of GA aircraft. The FAA’s statutory mandate does not, however, include requiring that GA aircraft are covered by liability insurance. NTSB is responsible for investigating all civil aviation accidents and major accidents and incidents in other transportation modes. Using the information gathered by its own investigators and in coordination with FAA, NTSB is responsible for determining an accident’s probable cause, issuing safety recommendations, and conducting safety studies. According to NTSB officials, if an NTSB official is not available at the scene of where the accident occurred, FAA gathers perishable data that are provided to the NTSB. However, NTSB is responsible for issuing a preliminary report and final accident report describing the history of the flight (e.g., date and time of accident, aircraft and accident type, purpose of flight, extent of pilot and passenger injuries, etc.) and findings of probable cause. NTSB also coordinates accident disaster-assistance activities, including providing information and assistance to accident victims (or their survivors), in the aftermath of an accident. The Office of the Secretary of Transportation (OST) within DOT is responsible for ensuring that commercial air carriers meet minimum liability insurance coverage amounts for liability, as required under federal law, and FAA has assumed this role pursuant to a memorandum of understanding with OST. The related regulatory requirement, which became effective in 1982, establishes minimum liability insurance requirements for air carriers. Commuter air carriers and air taxi operators are also required under federal regulations to have minimum liability insurance. While federal insurance requirements exist for commercial modes of transportation, the states generally regulate the business of insurance. No federal requirement exists for GA liability insurance, although as discussed later in this report, some states have liability insurance or similar requirements. Some countries require liability insurance for GA aircraft. Canada, for instance, requires commercial and GA aircraft owners operating aircraft with a maximum permissible take-off weight of more than 5,000 pounds to have liability insurance for death and bodily injury in the minimum amount of $300,000 (in U.S. dollars) multiplied by the number of passengers onboard the aircraft. Similarly, a European Union regulation requires liability insurance coverage for both commercial and GA aircraft when operating within, into, out of, or over the European Union member territories. When operating aircraft, owners and operators face financial risks, such as the risks associated with damage to the aircraft itself as well as those associated with death, injury, and property damage to third parties. Aircraft owners and operators, like many other individuals and organizations, may choose to purchase insurance in which the financial risks of an accident are transferred to an insurance company in exchange for a premium payment. Various aviation insurance products are available, such as hull insurance, which covers physical damages to the aircraft, including the engine, propeller, and all other systems and permanently attached equipment. Liability insurance covers death or bodily injury to passengers or persons on the ground as well as property damages caused by an aircraft accident. Aviation insurance policies for GA aircraft owners are generally sold to owners as a package, which include coverage for aircraft hull and liability. Additionally, GA pilots who do not own their own aircraft may also purchase their own liability insurance policy, commonly referred to as renters insurance. This type of insurance is designed to protect pilots against claims arising from bodily injury or property damages when they are deemed to have caused an accident. It is also designed to provide pilots with legal representation to defend themselves if they are sued, whether or not they are ultimately determined to be at fault for the accident. However, renter’s insurance is an excess insurance product that is secondary to the primary insurance policy of the aircraft owner, which is designed to pay for damages first. As such, renter’s insurance is not as comprehensive as aircraft owners insurance tied to the aircraft. For instance, in contrast to an aircraft owner’s policy, coverage for damages to third parties on a renter’s policy is typically not triggered unless the pilot was deemed to have been negligent in the operation of the aircraft, according to a principal insurance underwriter offering such policies. In addition to passengers on the aircraft or parties on the ground, insurance companies themselves may also sue pilots for damages, taking action to subrogate against the party responsible for losses paid. Apart from where liability insurance is required, whether GA aircraft owners or operators choose to purchase insurance depends, in part, on how much risk they are willing to assume versus the risk they need or desire to transfer (for a premium) to an insurance company. In particular, they may choose not to purchase coverage if they believe the coverage is too expensive for the amount of risk they bear. Based on our survey of state aviation officials and analysis of state statutes and regulations identified by such officials, as of April 2015, the majority of the states do not have liability insurance requirements applicable to GA aircraft owners and operators (see fig. 2). Five states have a liability insurance requirement that is applicable to at least some categories of GA aircraft owners and operators, and six states have some type of aircraft financial-responsibility requirements. Aviation officials we spoke with in these states generally commented that they did not know the history of why they have these requirements or how effective they have been in terms of ensuring liability insurance coverage because data are not collected to measure the effect of these requirements. Minnesota is the only state that has a liability insurance requirement applicable to nearly all GA aircraft owners. Every owner of aircraft in Minnesota, including GA aircraft owners, must show proof of insurance, with the minimum coverage requirements, when registering the aircraft with the state. While it is a misdemeanor under Minnesota law for an owner to operate an aircraft registered within Minnesota without the required liability insurance, according to state aviation officials, the state relies on self-reporting of liability insurance coverage during the aircraft registration process and does not systematically track violations. Four other states—Hawaii, Maryland, Oregon, and Rhode Island—have provisions applicable to GA aircraft owners and operators that require them to have liability insurance if they either hangar their aircraft at a state-owned airport or operate their GA aircraft for commercial purposes, such as leasing or renting out aircraft. For instance, according to a state aviation official, GA aircraft owners that base or hangar their aircraft at Rhode Island’s six state-owned airports for more than 90 days are required to register their aircraft with the state and have a minimum liability insurance coverage limit of $1 million per accident. In Hawaii, persons such as GA aircraft owners who rent a state hangar as well as air tour operators are required to maintain liability insurance. Six other states have some type of aircraft financial responsibility requirements. Under the aircraft financial responsibility requirements in California, Connecticut, Indiana, Massachusetts, and Virginia, GA aircraft owners and operators must demonstrate aircraft financial responsibility to the state by showing differing combinations of liability insurance, a bond, deposits of money or securities, or a letter of credit. Unlike the other five states, North Dakota does not specify how financial responsibility should be demonstrated. According to Virginia state aviation officials, most GA owners meet the Virginia requirement by purchasing liability insurance; however, aviation officials in California, Connecticut, Indiana, and Massachusetts told us that this requirement has not been enforced, due to lack of resources. See appendix II for more detailed description of states with minimum liability insurance requirements or aircraft financial requirements applicable for GA aircraft owners and operators.