Are Hilton Head Airport and Mammoth Yosemite Airport both public airports? 
Hilton Head Airport: Hilton Head Airport (IATA: HHH, ICAO: KHXD, FAA LID: HXD) is a public use airport located on Hilton Head Island, in Beaufort County, South Carolina, United States. Mammoth Yosemite Airport: Mammoth Yosemite Airport (IATA: MMH, ICAO: KMMH, FAA LID: MMH) is a town-owned public airport seven miles east of Mammoth Lakes, in Mono County, California.
yes