Eddie Andreini Sr. Airfield, officially Half Moon Bay Airport is a public airport in San Mateo County, northwest of Half Moon Bay, California, United States. The airport is on the Pacific Coast, south of San Francisco. History The Half Moon Bay Airport is about 20 miles south of San Francisco. It was built by the California State Highway Department for the U.S. Army in 1942 as an auxiliary airfield for Salinas Army Air Base. Known as Half Moon Bay Flight Strip, the airport supported Salinas AAF's ground support mission to train light observation and reconnaissance squadrons. These were light aircraft and fighters modified with camera equipment. Salinas Army Airbase also had the mission of conducting coastal patrols. As such, the airfield would have been garrisoned by a detachment of the 301st Base Headquarters and Air Base Squadron. With the reorganization of the Army Air Forces that took place in the first quarter of 1944, the site was transferred to Air Technical Service Command and garrisoned by its own unit, the 4159th Army Air Forces Base Unit (Air Base). The mission of this unit was to operate the airfield for emergency landings, transient aircraft, and training missions. Other than refueling aircraft, no aircraft services would have been available. On June 1, 1945, the War Department issued a five-year permit to the U.S. Navy to operate the Site as "Outlying Field, Half Moon Bay". Half Moon Bay field became an outlying field for Naval Air Station Moffett Field, to furnish facilities for utility aircraft providing target towing service for the Anti-Aircraft Training Center, Point Montara, California. San Mateo County acquired the airport from the Navy in 1947. It is an important business, transportation and emergency service asset to the community. Facilities Half Moon Bay Airport covers at an elevation of . Its asphalt/concrete runway, 12/30, is . Half Moon Bay Airport provides a variety of emergency service and response functions including: Air ambulance and Medevac flights; law enforcement and homeland security patrols; Coast Guard sea-rescue operations; and use as a disaster relief staging site for the airlifting of emergency supplies in the event that roads are closed during a disaster or emergency. Half Moon Bay Airport is home to about 80 aircraft and several related businesses. The airport is self-funded through airport user and business fees and receives no money from the county's general fund. In the year ending January 15, 2020,