Gillespie Field is a county-owned public airport 10 miles (16 km) northeast of downtown San Diego, in El Cajon, San Diego County, California.History Section reference dates.In 1942 the United States Marine Corps chose a site with 688acre east of San Diego for parachute training for the newly forming Parachute battalions. In September 1942 Camp Gillespie was completed and named in honor of Lieutenant Archibald H. Gillespie, a Marine officer who played a prominent role in the effort to separate California from Mexico in the 1840s. Three 256 foot high towers were built from which the paratroopers practiced their jumps.In February 1944, the camp was commissioned as Marine Corps Auxiliary Airfield Gillespie under the command of Marine Corps Air Station El Toro. MCAAF Gillespie soon became responsible for Camp Pendleton Outlying Air Field. Among the units that transited and trained at MCCAF Gillespie were VMSB-141, Air Warning Squadron 10 and the Navy's TBM-3 Avenger torpedo squadron VT-37.