Triangular UFO with 3 lights on each corner. No Sound. Low Flight Pattern.

It was some time in October of 1989.  My mom & I were driving through our neighborhood, off of Hwy 218.  As we approached our house we saw 3 distinct lights in the sky in the shape of a triangle.  We pulled up into the driveway and got out and walked back down to the street.  We saw the craft moving very slowly from west to east.  It was enormous, maybe the size of a football field.   It made no noise and seemed to block out the sky behind it.  It floated right above the treetops until it disappeared from our sight behind other houses.
WSOCTV news that evening reported that they had received calls of similar UFO sightings.  The newscaster reported this with skepticism and others have responded in the same manner as we’ve recounted this sighting over the years.
Source of report indicates that the date of the incident is approximate.  PD