The Avro Canada VZ-9 Avrocar was a VTOL aircraft developedas part of a secret U.S. military project during the Cold War. In the air, it would have resembled a flying saucer. Power for the rotor was provided by three Continental J69-T-9 jet engines. It's maximum speed was estimated at 300 mph (480 km/h).
Not 100% accurate representation as there isn't much material about the VZ-9 available.
I recommend adding "drone" and "quadrocopter" in the negative prompt to avoid it blending to a drone.