A short time ago I heard aircraft engines approaching. I went outside and listened for a second, looking in the direction the sound appeared to be comming from.
Soon I spotted movement above the trees and watched as a formation of helicopters flew over. They looked like they might have been H-46s and with the light from the full moon, the bottom of these copters looked like the clouds in the distance, a pale grey. They were not showing nav lights or any kind of visible beacons but were followed by another helicopter with all its lights on.
A couple time previously I had heard the same noise but never made it outside in time to see them. It looked like they were heading for Herndon airport here in Orlando.