AN SMA FREIGHTER PLT LEFT HIS ENG RUNNING WITHOUT TIEDOWNS OR CHOCKS WHILE HE UNLOADED THE ACFT. HE WAS THE SOLE OCCUPANT OF THE ACFT; A C206G.

Narrative

I WAS FLYING A TURBO CHARGED CESSNA 206 (TU206G). WHILE STOPPED AT DEER VALLEY; I LEFT THE ENGINE IDLING AT ABOUT 700-800 RPM. I SET AND CHKED THE PARKING BRAKE. AFTER VERIFYING THE ENG RPM AND RECHKING THE PARKING BRAKE; I EXITED THE ACFT; RAN AROUND THE TAIL SECTION TO THE CARGO DOOR. WHILE UNLOADING THE 'DEER VALLEY' CARGO; A PERSON QUESTIONED MY DECISION TO LEAVE THE ENG RUNNING WHILE OFFLOADING CARGO. THE PERSON QUESTIONING MY DECISION PULLED IN FRONT OF THE AIRPLANE; EXPRESSED HIS DISAPPROVAL WHILE I CLOSED AND LOCKED THE CARGO DOOR. AFTER SECURING THE CARGO DOOR; I RAN AROUND THE TAIL TO THE PLT DOOR. THE PERSON THEN DROVE TO THE SIDE OF THE AIRPLANE I WAS ON WHERE HE AGAIN EXPRESSED HIS OPINION. I SAID 'OK' AND CLBED INTO THE PLT'S SEAT. HE AGAIN EXPRESSED HIS OPINION. I SAID 'I HEAR YOU.' THEN I CALLED GND CTL AND REQUESTED TAXI CLRNC. DUE TO A TIGHT TIME SEQUENCE; I ELECTED NOT TO WAIT FOR THE 3 MIN TURBO COOL DOWN PERIOD AND DETERMINED THAT I COULD SAFELY LEAVE THE 'COCKPIT' WITH THE ENG RUNNING. THE TIME I WAS AWAY FROM THE CTLS AMOUNTED TO ABOUT 1 MIN AND 30 SECONDS. I DON'T FEEL THAT THIS PARTICULAR CIRCUMSTANCE WAS UNSAFE. I HAVE SINCE LEARNED THAT THIS PROC IS NOT ENCOURAGED BY THE FAA OR MY EMPLOYER. IN THE FUTURE; I WILL REFRAIN FROM SUCH ACTIVITIES.