It started as a supposedly routine training flight, but within hours an American airman and his team were launching secret spy missions for Israel. More than 16 years after the event, the airman has agreed to talk about the reconnaissance missions flown from the Negev desert, on the understanding that his name not be disclosed.
The airman, a photo technician, says damage-assessment film taken by four United States Air Force RF-4C jets painted with Israeli markings was thought to be ''incredibly useful'' to the Israelis as they attacked the armies and air forces of four Arab nations. With US help, the Israelis gained strategic ground at a blinding rate in what has come to be known as the ''six-day war'' of June 1967.
The American airman, long separated from the Air Force, still recalls with emotion the excitement of switching from routine training missions to a real war. As he described it, he and his fellow airmen had been processing pictures of ''castles and bridges and the Rhine.'' They were with the 17th Tactical Reconnaissance Squadron of the 66th Tactical Reconnaissance Wing, based at Upper Heyford, outside Oxford in England.
In the early morning hours of June 4, 1967, the nine American airmen involved in the secret mission were roused out of their sleep and told they were flying to Moron, Spain, for a training exercise. At Moron, the men were told that they had been selected to go to the Negev to provide support for the Israelis. They were issued civilian passports and given manuals in plastic binders printed by Aero-Tech Corporation of Dallas-Fort Worth, Texas. If anything went wrong, they were to be considered civilian contract employees hired by the Israeli government. They exchanged their military clothing for plain fatigues.
By the end of the day on June 4, the men were on the grouNd in the Negev at an abandoned airfield southeast of the large Israeli air force base at Beersheba. The American airman recalls seeing the four American RF-4Cs arrive at the base. Each of the camouflaged jets bore Israeli Air Force tail numbers and a white Star of David on a blue background on the rear fuselage.
The next morning, June 5, the Israelis launched what has been described as the largest coordinated air attack ever undertaken in the Middle East. The RF-4 Cs, modified versions of F-4 Phantom jet fighters, began flying reconnaissance missions over bombed and burning air bases in Egypt, Syria, and Jordan.
According to the American airman, US pilots flew the planes. Israelis running the cameras and communications flew in the back seats of the twin-seat RF-4Cs. At the base, American technicians worked closely with Israelis. The Israelis did all of the photo interpretation, or analyzing, of the film that the US planes and pilots brought back to the base.
The airman said Israeli Air Force planes had gun cameras that shot battlefield footage but that these did not have anything like the capability of the cameras on the US RF-4Cs, which had various focal lengths and forward- and side-looking radar. The American planes were also able to fly at night, using their radar and infrared film to track movements of Arab troops and armor.
Why the secrecy? The airman said that years later he was bothered by this. He was, if anything, ''pro-Israeli'' to this day, he said. But was the United States there not only to help the Israelis but also to test its own equipment? Was this type of secret activity a constant in US foreign relations?
Part of the answer may be found in a new book on America's secret relations with Israel entitled ''Taking Sides'' by Stephen Green, who used more than 100 Freedom of Information Act requests to extract new information on this sensitive subject.
A principal source for Mr. Green's book was the US airman who participated as an enlisted man in the Negev mission. The airman was interviewed Tuesday by reporters from CBS news, United Press International, and The Christian Science Monitor.
In Green's book, published by William Morrow & Co., the author notes that in the early days of the 1967 war, Arab officials were charging that the US was supporting the Israelis with air strikes. The Arabs apparently had the right idea but the wrong operation.
As far as is known, no American weapons were used. But the Arab accusations angered Arabs throughout the Middle East and triggered attacks on US embassies and installations.
According to Green, with their military superiority, the Israelis did not need American aerial reconnaissance assistance to win the war. But, he writes, it did help them to achieve ''certain territorial objectives within a very finite, limited time.''
The American night reconnaissance on June 8 and 9, says Green, enabled Israeli commanders to ''accurately assess the Jordanian and Egyptian strength that remained and thus facilitated decisions about which units could be sent north to undertake the attack upon Syria, and exactly when these units could be safely moved.''
Green concludes that President Lyndon B. Johnson and his national security adviser, Walt Rostow, were most probably aware of the operations conducted by the painted-over RF-4Cs. Such operations would have required approval by the highest authorities.