How you know when you have witnessed Time Travel?

IF you see an unknown ship that is stationary and not moving on air land or sea and it just disappears suddenly and you do not hear a sonic boom from extreme acceleration you likely have just witnessed time travel.

When I witnessed this in 1992 in Mt. Shasta above the 1 acre of land and house I was renting then with my family at first I was drawn outside by a cacophony of 3 double bladed over 40 passenger capacity each military type of helicopters. They were chopping the air because I was at 3500 feet so they were likely at 5000 feet but because the air is thin and they likely were either carrying passengers observing this (potentially 120 in 3 helicopters) in formation they were making an incredible racket with 6 blades on 3 helicopters.

note: I looked at Google images and each rotor has three blades so that means 6 blades per helicopter and a total of 18 blades for three helicopters. end note

 So, then they stopped stationary 2000 feet above me. But then, I realized traveling with them was a flying saucer that looked like the print I had seen in 1974 at Bunny Flats in person this time.

But then, it disappeared with no sonic boom telling me that likely I had just witnessed time travel.

The helicopters had no military insignia and were not painted army green or blue with military insignia. Instead they were painted gray with no markings at all (ABOVE TOP SECRET) so no one could say who they were except that these looked like military helicopters  (Chinooks) like they used in Viet Nam for hauling 40 plus troops at a time to battles etc.

So, if you see a real ship and then it just disappears more than likely you witnessed time travel. Otherwise you are going to hear a sonic boom when something accelerates that fast. Also, it might be important to know that without time travel any acceleration or even right angle turns between 3000 to 5000 miles per hour would kill human occupants because you can't survive such extremes in speed during acceleration without blacking out or dying.

I was writing recently about how this is why so many drones and planes are no longer manned because what they do in combat would kill any human being now that was inside them. a human body simply under normal conditions cannot survive what our technology is capable of now on air land, or sea.

These are from Google Images and what a Chinook looks like. The ones I saw were painted grey with no numbers letters or insignia on them at all which means (above top secret).