“Of course, the optical effects noted in conjunction with the radar echoes would depend upon temperature effects. However, the lack of a temperature inversion in the type of data referred to by Mr. Keyhoe does not preclude the possibility that extremely sharp and localized inversions existed over the area, perhaps in close association or in conjunction with the regions causing the radar echo. The Weather Bureau data cited are not sufficiently accurate nor do the instruments used in obtaining the data have a sufficiently rapid response to measure such small inversions. Also, such data are usually obtained at only two definite periods during each day. “As the distance between Andrews AFB and the Washington National Airport is only some few miles, the refractive effects of a given disturbance might appear to be quite similar, and the position of the resulting ground echo on the two sets might coincide to a fair degree of approximation. However, as information about the degree of accuracy maintained in plotting echo position is not available to me, I cannot comment with any degree of intelligence. It does seem though, that with the observed echo speeds and radical direction changes, as well as the echo appearance and disappearance phenomena, that accurate scope coordination between the separate fields would be extremely difficult.”[VIII-9] _“Simultaneous” Radar-Visual Reports_ On the night of July 29, three days after the second Washington crisis, the radar installation of the Air Defense Command post near Port Huron, Michigan, had been tracking three F-94s as they made practice runs on a B-25 bomber. At 9:40 P.M. C.S.T., ground control picked up an unidentified target moving from north to south at a speed of about 625 miles an hour. The operators notified the pilot of one of the F-94s and vectored him in for an attempted intercept. The plane’s radar did not show the reported target, but when the plane had climbed to a height of 21,000 feet, both the pilot and his radar man saw a brilliant multicolored light, many times larger than a star, close to the northern horizon. At the same time the plane’s radar picked up an echo in the north; it disappeared after thirty seconds, although the light was still visible dead ahead. As the pilot began the chase, the light changed color from bluish white to reddish and slowly diminished in size as though it were moving away. The pilot pursued the light for about half an hour without gaining on it, and eventually had to return to base. The ground radar, meanwhile, had been trying to keep track of events in the sky. When the chase began, the target appearing on ground radar had first made a 180-degree turn and reversed direction from south to north; it had then moved erratically, doubling its speed instantaneously, and then slowing down. It once seemed to reach a speed of about 1400 miles an hour, then slowed to about 300 mph, and disappeared from the scope shortly after the plane had returned to