ufo sighted just north of muncie,indiana

On a warm, clear, summer evening, I was driving home. I lived in a house about 2 miles outside of the town of Muncie,Indiana. 80,000 people. I was passing the municiple airport, and saw an object hovering, only 20 feet above a 1 story house, which sat right next to a large subdivision of about 400 homes. Object was less than 1 mile from airport. I drove towards it, in my truck. When I got within 500 feet, I turned my lights off and drove, staring at this object. I came within 300 feet when I realized it made absolutely no sound. It rose about 30 feet, then took off towards the northwest sky and dissapeared in seconds. All without a sound. Object had three lights on the bottom. Red,green,blue. Thought it was a chopper at first. But why hover silenlty, 20 feet over a house, and then take off from a dead stop, to out of sight in 3 seconds? Sonic booms are common in this area, but this was silent.