Narrative:

I was flying a scenic tour with 2 guests on board approaching lake coeur D'alene from the northwest near the veterans memorial bridge. As we neared the lake after our flying I-90, we began a slow right turn of about 90 degrees to fly along the north shoreline of the lake. About 45 degrees into the turn, the commander appeared at 12 O'clock position and about 200 ft. He was in a fairly steep climb and at a fairly high speed as he overflew us. I lowered the collective to attempt a descent, but his climb was more effective given the limited time. The event occurred so quickly, my passenger did not even realize what had happened. The commander continued northbound and ultimately made a radio call for landing at coeur D'alene. We were both outside the CTAF at coe. There is very little traffic normally in the area of the incident. Seaplanes operate in the downtown area about 3 mi west. I have not yet been able to contact the pilot of the commander to determine if he actually saw us or not. I did not have my transponder on since I was not going into class C airspace. I will have it on during any future flight. I did not announce my progressive position on my tour route. I will announce progressive position at least at points prior to making any turns or changes in headings or altitudes. I am thankful for the opportunity to share this information with you and am hopeful that it may be helpful.

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Original NASA ASRS Text

Title: NMAC BTWN A TOUR R44 HELI AND A LOW FLYING COMMANDER 112TCA 6 MI SE OF COE, ID.

Narrative: I WAS FLYING A SCENIC TOUR WITH 2 GUESTS ON BOARD APCHING LAKE COEUR D'ALENE FROM THE NW NEAR THE VETERANS MEMORIAL BRIDGE. AS WE NEARED THE LAKE AFTER OUR FLYING I-90, WE BEGAN A SLOW R TURN OF ABOUT 90 DEGS TO FLY ALONG THE N SHORELINE OF THE LAKE. ABOUT 45 DEGS INTO THE TURN, THE COMMANDER APPEARED AT 12 O'CLOCK POS AND ABOUT 200 FT. HE WAS IN A FAIRLY STEEP CLB AND AT A FAIRLY HIGH SPD AS HE OVERFLEW US. I LOWERED THE COLLECTIVE TO ATTEMPT A DSCNT, BUT HIS CLB WAS MORE EFFECTIVE GIVEN THE LIMITED TIME. THE EVENT OCCURRED SO QUICKLY, MY PAX DID NOT EVEN REALIZE WHAT HAD HAPPENED. THE COMMANDER CONTINUED NBOUND AND ULTIMATELY MADE A RADIO CALL FOR LNDG AT COEUR D'ALENE. WE WERE BOTH OUTSIDE THE CTAF AT COE. THERE IS VERY LITTLE TFC NORMALLY IN THE AREA OF THE INCIDENT. SEAPLANES OPERATE IN THE DOWNTOWN AREA ABOUT 3 MI W. I HAVE NOT YET BEEN ABLE TO CONTACT THE PLT OF THE COMMANDER TO DETERMINE IF HE ACTUALLY SAW US OR NOT. I DID NOT HAVE MY XPONDER ON SINCE I WAS NOT GOING INTO CLASS C AIRSPACE. I WILL HAVE IT ON DURING ANY FUTURE FLT. I DID NOT ANNOUNCE MY PROGRESSIVE POS ON MY TOUR RTE. I WILL ANNOUNCE PROGRESSIVE POS AT LEAST AT POINTS PRIOR TO MAKING ANY TURNS OR CHANGES IN HDGS OR ALTS. I AM THANKFUL FOR THE OPPORTUNITY TO SHARE THIS INFO WITH YOU AND AM HOPEFUL THAT IT MAY BE HELPFUL.

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.