Curiously, the FAA radar readings that were sent to him — taken from three stations 150 km apart — paint a peculiar picture of the early morning sky over western Pennsylvania. The below animation shows 30-40 unknown targets that were tracked from 2 a.m. to 4:30 a.m. on that particular morning.
Mr. Schultze explains the radar images:
Approximately 3 dozen radar reflective slow speed skin paint targets are seen transiting the area of interest to the northeast in an operational pattern that is consistent with what can be argued is a coordinated search or survey mission extending over 10,000 square nautical miles of Western Pennsylvania.
According to Schultze, the targets lacked transponders and had signatures different from the few planes that were present in the area at the time. The targets were cruising from south to northeast at an altitude of about 1,200 to 1,500 meters (4,000 to 5,000 feet), which is well within the flight height of migratory birds.
The bird hypothesis is not favored by bird expert Dr. Greg Butcher, however, who notes that migratory birds are heading south, not north, in October. Also:
[...] what you see with flocks of birds on radar is, they form a big cloud. It looks like a mushroom cloud. I don’t know what we’re looking at, but they’re not birds.
So what are they then? We’ll probably never know. This is yet another case among many others where strange objects that can’t be explained have been picked up by radar. Unfortunately, those who are interested in investigating these cases lack the resources and those who have the resources (FAA), lack the interest…
(Source: De Void at Herald-Tribune)