Around the web and in the Disclosure video in the first link, there are several reports of radar returns showing UFOs travelling at thousands of mph. The one thing they all have in common is that they don't explain how they came to that conclusion.
On the Disclosure video, one former army air traffic controller was talking about an incident in 1958 in which a bunch of UFOs moved away at, by his calculation, 17,000 mph.
He also said that the UFO he heard sounded like a "pulsating transformer". A nonsense phrase.
In the late 50s, the Army radar was quite primitive. He was probably using the SAGE radar. I say this because he said he was stationed at the Nike Ajax missile base close to Olney, MD. Nike bases used the SAGE radar back then.
He said he picked up the UFO "just outside the ground clutter". From one sweep to another, the UFO (UFOs?) moved to 2/3 off his radar scope. And therefore it (they) was moving at 17,000 mph.
SAGE used many different kinds of radar over the years, but in the 50s, the radar freq was way down in the Mhz ranges. It could have been as low as 214 Mhz, and probably no higher than 450 Mhz.
Because it was mostly likely the SAGE system, I am using
this document for source material.
A "radar mile" is 12.36 microseconds. So if you have a pulse width of about 12 microseconds, your radar is blind for out to one mile from the transmitting antenna. A 10 microsecond pulse width means your radar is blind out to 5/6 of a mile, while a 75 microsecond pulse width means your radar is blind out to about 6 miles.
So that is one element of your "ground clutter".
The other aspect of ground clutter is your operating frequency, which I mentioned above was pretty low for radar back in the 50s. Low radar freqs mean lots of ground clutter for a long way out. That is why as the technology improved, the frequencies rose and the pulse widths shortened.
I've never worked with a radar as low in freq as what the SAGE radar must have been back then. The lowest freq I worked with was 2 Ghz, and that had five miles of ground clutter.
In addition, this former air traffic controller said he was just outside Olney, MD and got a call from a guy at the Gaithersburg missile base who said the UFOs were right above his head. The controller turned on his radar and the blips were "just outside the ground clutter". According to Mapquest, the distance from Olney to Gaithersburg is 11.93 miles.
So based on my radar knowledge and everything I wrote above and a map, the UFOs must have been about 12 miles from his radar transmitter.
The radar sweep of a SAGE radar, and most of the radars of that time, was 15 seconds.
The controller said the UFO moved from "just outside the ground clutter" to 2/3 of the way off his screen in one sweep, or 15 seconds.
But first, he marked the location of the UFOs. "And then for a few minutes later, they took off." So he made his mark a few minutes before he noted them taking off and then making his calculation.
He does not say what scale he had his radar set to. I have been unable to find what scale settings the SAGE radar operated at.
But to move at 17,000 mph, the craft would have to move at 4.722222 miles per second.
In 15 seconds (one radar sweep), they would have had to move 70.83333 miles.
Roughly 12 miles of ground clutter plus roughly 71 miles of movement gives 83 miles from the transmitter.
83 is 2/3 of 124.5. So his range must have been set at 125 miles.
The pulse repetition frequency (PRF) of a radar determines its range. According to my source document, the SAGE radar that operated at 425-450 Mhz (FPS-35), had a PRF of 333.
The PRF will tell you the maximum detectable range of a radar, but I'm out of time. I'll have to get back to that.
Anwya, I think it is important that he did not note their movement until a few minutes after marking his screen.
