While stationed at Long Binh Army Post in the Rebublic of Vietnam in about 1972, two other soldiers and I witnessed an object that seemed to fly low and slow across the post.
The object may have been cylindrical but actually had no definate shape. The object looked like heat waves but with a sort of cylindrical shape.
My buddies and I asked each other if we were seeing what the others were seeing, and we agreed that we were all seeing the same thing. The object looked to be only a few hundred yards away and a few hundred feet off the ground. It was traveling slow and we heard no sound. It maintained the same speed and direction until out of sight.
It is my opinion that the object was camoed or cloaked in some fashion to keep from being seen. I have never heard of another UFO report of a similar object although I don't keep up with UFO sightings.