Typed out too big a wall of text (1/?)
Excellent quote to remember for this subject, pic related.
So I'll go ahead and share my story since this is a comfy place for it and velocity holds a special place in my heart. I have without a doubt seen what people commonly call the TR-3B and it was a fantastic violation of the physics you'll learn in public schools. Let me preface with I'm pretty familiar with a wide array of aircraft, I can easily pick out the silhouette of an F117 vs a B2, this thing was certainly neither. I've been buzzed by an F117 at low altitude more than once, you KNOW they are there by the sound.
So, circa 07, I was out night hiking with a friend, we happen to be headed back to the parking lot and luckily facing in JUST the right direction to see this bulking black triangle silhouette come into view from right over the hills in front of us, this thing was LOW, maybe 4-500 yards off the deck, if even. Instantly recognizing that I don't know anything that takes up the footprint of about 3 Boeing 747s in a delta formation, I thought that was pretty odd. Hard to estimate it's inbound velocity, because right as it came over the hill it just snapped to an absolute standstill hover. This is the first interesting point, because to the physics we are taught, this shouldn't be a possibility, momentum is mass*velocity. So if you have this enormous craft, its probably safe to say it's structure alone has got a fair amount of mass, blimps and other lighter than air craft can not move like that btw; not ours anyhow 😅. An object has this momentum when it is in motion, to make things more simple here we should ignore wind resistance and just pretend the craft is Flux pinned to Earth's magnetic field at it's fixed altitude. Momentum is directly proportional to the mass and velocity, in order to arrest momentum, an acceleration force of equal magnitude must be applied in the direction directly opposite of said momentum. Reminder that acceleration is a change of velocity over time, where the acceleration forse is INVERSELY proportional to the time interval of velocity change, simply put, the faster you change your speed, the more acceleration force. With that nerdshit out of the way, going all stop INSTANTANEOUSLY from lets even call it 200mph would be subjecting the airframe, all on board equipment, and especially the crew to that same tremendous acceleration force, well more than enough to make a person feel sick, and iirc eyes out G-forces are the worst for us squishy meat bags. At this point you were probably thinking I was done talking about physics, but now we are staring up at this behemoth of a triangle just hanging there in the sky, much in the same way bricks don't. If it's not a lighter than air craft, that was another conundrum. Lift is generated by a differential of air pressure that is developed as air flows faster over the longer path on top of a wing, creating low pressure, and slower over the bottom thus creating the high pressure zone that forces the wing to loft itself upwards as the wing travels forward… but this thing is just sitting there like it belongs.