I have a good video of (what my friend on here told me) was probably the TR3B. It was silently hovering over a power substation, then the pilot seemed to notice me. Took off, floating directly overhead. It was low and slow enough to faintly hear some kind of bizarre sounding propulsion system or “exhaust“ signature. Although it could have been the sound of air getting displaced by the craft in flight. Idk.

Thought it was incredibly cool at the time and I have wanted to fly one ever since.