Disk seen hovering over residential area in O'Fallon, IL

It was around March of 1983.  It was early evening... between 8 and 9 pm.  My best friend, her mother, aunt and I were coming home from the mall (St. Clair Square).  She had gotten my ears pierced for my birthday.  We were driving along Rt. 50, going east.  We saw something hovering over the trees towards the north.  It was a disk... huge... with lights all around it.  We tried to get as close as we could, but it was hovering in a residential area (in O'Fallon, IL) behind some houses.  We stopped and watched it for a few minutes (no more than 2 or 3), then it dashed away, quicker than anything I had ever seen move.  Then was a dot in the sky and then totally disappeared.  No sound came from it, which we thought was very strange.
 We talked about it for a while and everyone thought we were crazy, so we left it alone.  It was close to Scott AFB as well... but we all knew that it wasn't AF related.
 Unfortunately, the 2 older women are both deceased.  However, I spoke about it to the aunt's husband this past summer, and he confirmed that his wife had told him about this encounter.
Witness indicates that date of incident is approximate.  PD