Every so often I see an unmistakably small, quad engine aircraft on the approach path to KDCA from my vantage point by the Vienna Metro in the DC area. They appear to be BA 146 / Avro RJ or very similar in shape and size - however I never see any log of this on flightaware arrivals. The last sighting at roughly 7:30pm at 4/14/2015 (yesterday) prompted me to inquire here since there is no record otherwise (here or similar aviation websites). Anybody know more about this?
(or could I be mistaking a military craft going to AFB? These aircraft are going the exact same flight path as the many USair and JetBlue descents before and after)