This incident was discussed in posts #1506-1527 of this thread.
NTSB Aviation Investigation Preliminary Report - N879RW (RPA), UH-60 (PAT23)
…but around this time, PAT23 had checked in with the JPN Heliport Tower (HT) LC controller and was attempting to land on the helipad without a landing clearance. When the JPN HT LC controller queried the crew to ask who had cleared them to land, the crew advised they were executing a go around and that DCA ATCT had cleared them to the helipad.