Las Vegas, NevadaOctober 1947

On October 8 or 9, 1947, during daytime in Las Vegas, Nevada, an Air Force Reserve pilot reported observing a trail appearing high in the sky at an estimated speed of 100-1000 mph. The object produced the trail but was not visible. The trail was white as a cloud and dissipated in fifteen to twenty minutes. The object proceeded in a straight line, made an approximately 109-degree turn of radius five to fifteen miles, then proceeded away toward the direction of first appearance. Weather was almost cloudless. The Air Force concluded it is difficult to understand why the pilot attached importance to this sighting. The trail was likely caused by an ordinary aircraft flying normally at altitude too high for itself to be visible, but in the best altitude range to form vapor trails 20,000 to 45,000 feet.