 He found that the radar witnesses still disputed the Air Force explanation, but that did not stop the report from agreeing with the temperature inversion/mirage explanation.Ruppelt related that on July 27 the control tower at Washington National had called the control tower at Andrews AFB and notified them that their radar had an unknown object just south of the Andrews control tower, directly over the Andrews AFB radio range station.According to Ruppelt, when the Andrews control tower personnel looked they all saw "a huge fiery-orange sphere" hovering over the range station.