Wedge shaped UFO with no sound and not lights traveling very slowly over the highway.

In the summer of 1994, I saw a pair of wedge shaped wings with a portal of some kind in the center pass over KY 114.  It was traveling very slowly 10-15 MPH as it went west towards the nearby Wal-Mart.  I saw it for about 30-45 seconds as it traveled into low hanging clouds.  I could see it well as I was about 300 feet away.  It was bigger than a 747. It was so low I could see the trees of the nearby hill above it and below it.  There was no sound and no lights on the object.  The bottom of the craft seemed to be trying to match the night sky which was black due to illumination from nearby lights located at the civil war sight just off KY 114.  It appeared a shade darker than the night sky.  I was talking to a friend at the time who also saw the object.  The wings appeared gray and the craft was more of a trapezoid with wings than the shape of a triangle.
Witness indicates that the date of the sighting is approximate.  PD