The federal government last looked at the feasibility of putting commercial flights at the El Toro Marine Corps Air Station in a report made public in 1984.
The Department of Defense and the Department of Transportation concluded after that study that "joint use" was not a viable alternative for El Toro.
Among other things, investigators concluded that residents living around the air station "tolerate the military" with its limited number of flights, but those same residents might oppose a steady stream of commercial jetliners plus military fighters.
About 175 military aircraft are based at El Toro, including F-4 Phantoms, A-4 Skyhawks, A-6 Intruders, F/A-18 Hornets and KC-130 transports, according to the report.
"El Toro is primarily a training base," noted the report, which was prepared by HH Aerospace Design Co. of Cambridge, Mass., for the U.S. departments of defense and transportation. "Among the tasks assigned to El Toro are to provide search and rescue, direct support aircraft as required by fleet Marine units and to store and maintain assigned ammunition. It is also an operational base used for staging aircraft throughout the Pacific area and by transient aircraft in the continental United States."
In that report, the military pointed out that the parallel runways at El Toro could not be used simultaneously because separation is not great enough. It also said that during much of the year fighters are practicing aircraft carrier landings, which are incompatible with commercial air traffic.
"Bombs, forward firing missiles, machine guns and rockets are stored on the base and, at certain times, loaded on aircraft," it noted. The report quoted military officials as saying El Toro was "unfit" for joint use.
The study said El Toro is a crowded community with airspace and facility limitations.
"New construction has surrounded the airport," the report quoted the military as saying. "Neither can the airport expand nor can the crowded airspace problem be properly solved. Any significant increase of activity, military or civilian, would not be tolerated by the surrounding communities."
Furthermore, the report said, "(The) base is afraid of long-term buildup of civilian traffic once the civilians get 'a foot in the door.'
"In that case," the report added, "El Toro as a training base ceases to exist."
The Department of Defense has approved the conversion of 24 military airfields for "joint use" by the military and commercial aviators. All joint-use air bases have had the support of the Defense Department, and one military source said "no joint-use agreement has ever been approved without a DOD blessing."
The Department of Defense policy says it will consider the joint use of a facility "when it does not compromise military response, security, readiness or safety."
Generally, the policy says, an airfield will be considered for joint use "if it does not have a nuclear alert force, pilot training (either student or qualification), nuclear storage or a major classified mission.
El Toro has pilot training and the missions of some of its many squadrons within the air wing are sensitive.
Usually joint use is not approved if military and civilian aircraft have to be located in the same area, if entrance to the civilian terminal has to be made through the base and if the conversion calls for increased airfield operating hours.