A user benefits economic impact model of general aviation (GA) travel is developed using data for five publicly owned airports in North Carolina. A 1994 survey of GA users concerning flight origins, destinations, intermediate stops, and local expenditures is geographically represented with TransCAD 3.0, a geographic information system. Minimum-time road paths for these flights are also computed. User costs including passenger value of time, local ground transportation, overnight costs, and expenditures for crew and passengers are then estimated, and costs and travel times for the two modes are calculated for each airport. Findings are compared with the traditional jobs-based method of estimating airport impacts. Results indicate that as the passenger value of time increases, travel using the general aviation mode becomes more advantageous than is automobile travel. In addition, as the trip length increases, more time spent in traveling induces overnight stays and thus travel expenses rise considerably. However, uncertainty in user expenditures is large (±20 to 40 percent) for typical values of the key inputs. The study concludes that although the user benefits method of estimating aviation impacts is promising, more research is needed to refine the method for use in practice.