black triangle over "Tesla" concert in Noblesville,IN 1992

I was at the Deer Creek ampitheatre watching a concert for the rock band "Tesla" and I was lying down in the lawn looking up at the stars.  As I was looking up when a large black triange-shaped craft with a yellow/white lights at each of the corners with a red pulsating light in the center of the craft.  It was flying very low, slower than most small airplanes in a northeast to southwest direction in the general path I-69 follows into Indianapolis.  As the craft flew towards Indy, I could see its silhoutte against the city lights and I saw a small red orb-like light fly up to the craft then a short time later fly back towards the ground.  At the time I didn't think too much about what I saw, but I seen the same craft that was seen in Belgium, Illinois, etc., and when I realized that others have seen this craft I knew I wasn't imagining this thing.  In my opinion, if this craft is one of ours then I believe it's some sort of low and slow stealth reconnaise craft.  This football field sized craft obviously wasn't concerned with being seen since there was probably 10,000-15,000 people at the show.  But during a loud, bright rock concert not too many people are paying attention to the sky.
Witness elects to remain totally anonymous.  PD