Fly in your own plane or contract a plane. Mariposa Airport, which accepts only private planes and chartered planes, is half an hour away. For more information on Mariposa, call (209) 966-2143. Merced Airport, a little furthur away, also accepts private and chartered planes. Both airports say that no formal arrangements are needed to fly in.
Take a small airline to Merced, which has one commercial airline, Great Lakes Airlines (see Resources). This airport is an hour and a half from the entrance to the park.
Fly with a major airline; you have three choices. Fresno is the closest major airport at 1 1/2 hours, followed by Sacramento at 2 1/2 hours and San Francisco at 3 hours. From June to October, the east gate to the park is open, allowing for a 2-hour drive from the Reno Airport as well.
Rent a car and drive to the park from the airport to the park. All of the airports mentioned above have a place to do this.