Narrative:

Approach was made from annapolis heliport to bwi TCA. Clearance was given by tower on 119.4. I transitioned through the TCA at 500 ft MSL direct to the inner harbor area. Bwi turned me over to approach on 119.7 and we were approved to the inner harbor area direct and cleared to orbit the area. I have had more than 10 hours of night flying in this area without incident. This flight was for training purposes with a student. I had just flown up the harbor along the shoreline at approximately 400 ft MSL and crossed inland and orbited the orioles camden yards baseball stadium which was empty, then proceeded in a counterclockwise orbit of the downtown where we made visual contact with another helicopter. The other helicopter then flashed his landing lights and began to follow our helicopter and flew within a few hundred yards of us. I was still in contact, both radio and radar, with bwi approach when the pilot of the other helicopter made contact with bwi approach and idented himself as a police helicopter and was following 'a helicopter through downtown, flying very low, obviously avoiding radar contact and breaking every far in the book.' bwi approach told him that they (bwi approach) were 'working' us. I was then instructed to switch to 123.02 by bwi approach at the police pilot's request. After switching to 123.02 and making contact the police pilot told me 'you were flying too low and had made no radio contact with me and are causing hazard to persons on the ground and himself.' I responded by asking him what I had done wrong, and he responded 'I know what you did and so do you.' I finished our communication by apologizing and explaining that bwi approach had not terminated radio contact or advised me of any other frequency in use. I then recontacted bwi approach and left the TCA immediately and remained 500 ft and above. I am not aware of ever violating any far including far 91.119 or 91.13. I have some experience in this local area and operating at these altitudes. Also, I have never had an incident or accident.

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Original NASA ASRS Text

Title: HELI INSTRUCTOR WITH STUDENT AND IN CONTACT WITH ATC CALLED ON CARPET BY POLICE HELI FLC FOR LOW FLYING.

Narrative: APCH WAS MADE FROM ANNAPOLIS HELIPORT TO BWI TCA. CLRNC WAS GIVEN BY TWR ON 119.4. I TRANSITIONED THROUGH THE TCA AT 500 FT MSL DIRECT TO THE INNER HARBOR AREA. BWI TURNED ME OVER TO APCH ON 119.7 AND WE WERE APPROVED TO THE INNER HARBOR AREA DIRECT AND CLRED TO ORBIT THE AREA. I HAVE HAD MORE THAN 10 HRS OF NIGHT FLYING IN THIS AREA WITHOUT INCIDENT. THIS FLT WAS FOR TRAINING PURPOSES WITH A STUDENT. I HAD JUST FLOWN UP THE HARBOR ALONG THE SHORELINE AT APPROX 400 FT MSL AND CROSSED INLAND AND ORBITED THE ORIOLES CAMDEN YARDS BASEBALL STADIUM WHICH WAS EMPTY, THEN PROCEEDED IN A COUNTERCLOCKWISE ORBIT OF THE DOWNTOWN WHERE WE MADE VISUAL CONTACT WITH ANOTHER HELI. THE OTHER HELI THEN FLASHED HIS LNDG LIGHTS AND BEGAN TO FOLLOW OUR HELI AND FLEW WITHIN A FEW HUNDRED YARDS OF US. I WAS STILL IN CONTACT, BOTH RADIO AND RADAR, WITH BWI APCH WHEN THE PLT OF THE OTHER HELI MADE CONTACT WITH BWI APCH AND IDENTED HIMSELF AS A POLICE HELI AND WAS FOLLOWING 'A HELI THROUGH DOWNTOWN, FLYING VERY LOW, OBVIOUSLY AVOIDING RADAR CONTACT AND BREAKING EVERY FAR IN THE BOOK.' BWI APCH TOLD HIM THAT THEY (BWI APCH) WERE 'WORKING' US. I WAS THEN INSTRUCTED TO SWITCH TO 123.02 BY BWI APCH AT THE POLICE PLT'S REQUEST. AFTER SWITCHING TO 123.02 AND MAKING CONTACT THE POLICE PLT TOLD ME 'YOU WERE FLYING TOO LOW AND HAD MADE NO RADIO CONTACT WITH ME AND ARE CAUSING HAZARD TO PERSONS ON THE GND AND HIMSELF.' I RESPONDED BY ASKING HIM WHAT I HAD DONE WRONG, AND HE RESPONDED 'I KNOW WHAT YOU DID AND SO DO YOU.' I FINISHED OUR COM BY APOLOGIZING AND EXPLAINING THAT BWI APCH HAD NOT TERMINATED RADIO CONTACT OR ADVISED ME OF ANY OTHER FREQ IN USE. I THEN RECONTACTED BWI APCH AND LEFT THE TCA IMMEDIATELY AND REMAINED 500 FT AND ABOVE. I AM NOT AWARE OF EVER VIOLATING ANY FAR INCLUDING FAR 91.119 OR 91.13. I HAVE SOME EXPERIENCE IN THIS LCL AREA AND OPERATING AT THESE ALTS. ALSO, I HAVE NEVER HAD AN INCIDENT OR ACCIDENT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.