Lights red and white hovering silently then disappearing , reappearing and disappearing again. Then loud propulsion noise lasting 2 s

Multi color lights alternately appearing , disappearing in the sky above the treeline much like a drone array only no structure seen and much larger in width than a common drone. When I went to the window to get a closer look I heard a loud powerful propulsion lasting a couple seconds then no more to report. During the time I saw lights there was no sound just silence. After the propulsion noise no more sighting.