The same held true, and still does, for the odd array of lights used on tanker planes during aerial refueling operations. Some phenomena are so rare and so little is known about them that they are always UFO's. The most common is the disc following the airplane. I've never heard an explanation for this phenomenon but it exists and I've seen it on three occasions. Maybe a dense blob of air tears off the airplane, floats along behind, and reflects the sunlight. Whatever it is, it gives the illusion of a saucer "chasing" an airplane. Sometimes it's steady and sometimes it darts back and forth. It only stays in view a few seconds and when it disappears it fades and looks for all the world as if it's suddenly streaking away into the distance. Birds, bees, bugs, airplanes, planets, stars, balloons, and a host of other common everyday objects become UFO's the instant they are viewed under other than normal situations. Then there is radar. This poor inanimate piece of electronic equipment has taken a beating when UFO proof is being offered. "Radar is not subject to the frailties of the human mind," is the outcry of every saucer fan, "and radar has seen UFO's." Radar is no better than the radar observer and the radar observer has a mind. And where there's a mind there is the same old trouble. If the presentation on the radarscope doesn't look like it has looked for years a UFO is being tracked. Radar is temperamental. The scope presentation of each radar has certain peculiarities and an operator gets used to seeing these. Occasionally, and for some unknown reason, these peculiarities suddenly change. For months a temperature inversion may cause 50 or 75 targets to appear on the radarscope. The operator has learned to recognize them and knows that they are caused by weather. They are not UFO's. But overnight something changes and now this same temperature inversion causes only one or two targets. The operator isn't used to seeing this and the targets are now UFO's. Many times we'd stumble across the fact that after the first report of a UFO being tracked on radar the same identical type of target would be tracked again, many times. But by this time the operator would have learned that they were caused by weather and it wouldn't be reported to us. It is interesting to note that, to my knowledge, there has never been a radar sighting classed as "unknown" when radarscope photos were taken. The reason is simple. The radar operator can take ample time to re-examine what he had to interpret in seconds during the actual sighting. Also, more experienced radar operators have a chance to examine the scope presentation. Mixed in with the fact that there are few really qualified observers on this earth is the power of suggestion. About the time someone yells "UFO!" and points, all powers of reasoning come to a screeching halt. We saw this happen day after day.