Since I've spent my whole life in the Greater Akron area, over the last 60 years I've probly seen various blimps fly over head at least a 1000 times, and I'm more than a little familiar with them. All of GoodYears blimps I've seen used propeller driven, piston engines that sound just like most any other propeller driven aricraft. With the exception of one, The Spirit of GoodYear that was Turbine powered, and it simply sounded like a slow moving Turbo prop aircraft. That is until it crashed about 3.5 miles from my house.
A few years ago I had the pleasure of a 45 minute flight in the GoodYear Blimp stored at the Wing Foot Lake Hangar just 4 miles down the road from me.
As for the UFO sighting I experience in 1966, it was just that. An unadentifiable flying object, nothing more, nothing less.
It had no wings, it wasn't a "silent" helicopter, it wasn't a hot air balloon, or a military drone.
I'm not saying it was extraterrestrial, just never saw anything like it before or after.
I just thought it was interesting that my only "close encounter" happened just a couple days before the well documentated event in Portage County back in 1966.