Some type of Electrically Propelled, composite fuselage, Craft floated overhead at a slow speed, heading toward Ft. Hood Army Post.

I had just started fishing around 8:15 in the morning, 1st day of leave for vacation.  I was just below the dam several thousand feet downstream and heard some type of rythmatic Electrical Popping sound getting louder. There was nothing but heavy woods for over a mile around this area in 1991.  I saw a large green sphere forming in my vision through the trees. It was at tree top height and going very slowly. The sound was coming from the top.  I smelled rancid ozone.  The sound was over 115db but less than 130db. It was definitely an electrical short, with loud crack to the popping.
I was an active duty C-130/C-23 Crew Chief in the USAF at the time and could see conventional AN517 type Phillips heads fasteners around the single Window. I got within 100 feet of it as it went by overhead.
The window appeared milked, crazed or distorted like Aviation poly-carbonate windows when they get old.  After it passed 3 UH-60 Helicopter followed several thousand feet behind.   The electrical Arc sound was drowning out the sound of the UH-60's.  There were people setting on the UH-60 floor at the door ledges looking outward on the UH-60s.   I was straight under them when I noticed the legs hanging over the side.  The soldiers were looking outward, I suspect for witnesses.  I was in heavy trees and they were about 500ft AGL following the Sphere which was still about 80 feet AGL.  I lost vision of it over the horizon of the dam.