Notice, we patented how the ETs do this back in 1994:
"There are a lot more sightings than have been made public," Ratcliffe said. "Some of those have been declassified. And when we
talk about sightings, we are talking about objects that have seen by Navy or Air Force pilots, or have been picked up by satellite imagery that frankly engage in actions that are difficult to explain. Movements that are hard to replicate that we don’t have
the technology for. Or traveling at speeds that exceed the sound barrier without a sonic boom."
SLICK SAUCERS
Or
“An analysis is offered as to how extra-terrestrial alien "saucers" ease their passage through our low atmosphere at supersonic speeds without sonic "booms"
and what electromagnetic radio frequencies may leak from their related (and now patented) Aerodynamic Augmentation Device (AAD).1 Explained
are UFO related enigmas like magnetic fields, glowing saucers and the lack of "sonic booms" during high speed encounters.2 Possible
UFO related "radar" transmission frequencies are postulated. A method to distinguish alien vs. human produced crop circles is considered.‘