Narrative:

While flying an R22B helicopter as a spotting aircraft (marijuana spotting) for a sheriff's department, I was requested by the spotter, a deputy sheriff, to set down in a field so that he could relieve himself. After landing, the deputy asked if I needed to go. I said no, he asked if I was sure, I reconsidered and said yes. While the deputy was exiting the aircraft I locked down the control friction locks for the cyclic and collective, turned off the governor and reduced RPM to approximately 80 percent, and also exited the aircraft. While 'relieving' ourselves next to the aircraft the deputy was apparently standing on the skid. He suddenly stated, 'I just felt the skid rock up under my foot.' I turned to the aircraft to see the deputy also facing it and started to enter the aircraft. Before I could enter the aircraft rocked backwards bringing the nose a substantial distance up off of the ground. The engine RPM increased substantially (by the noise level). The aircraft lifted off the ground, rolled left and came to rest on its left side with sudden engine stoppage. In the sequence of events, the tail rotor also struck the ground. I was pushed forward and away from the aircraft and the deputy was pushed to the side, away from the aircraft, by the skid he was standing on. No injuries resulted. I feel that contributing factors were strong gusty wind conditions through the valley in which the incident took place. I can not explain the increase in RPM that apparently caused the aircraft to 'lift off' although I theorize that the aircraft tail rotor was taken off by ground contact which supplied increased power to the main rotor. I also realize that the control friction on this helicopter is probably not adequate to hold control surfaces in position in the absence of the pilot, and I should not have left the aircraft while it was running.

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Original NASA ASRS Text

Title: UNMANNED HELI LIFTED OFF, ROLLED, ACFT DAMAGE.

Narrative: WHILE FLYING AN R22B HELI AS A SPOTTING ACFT (MARIJUANA SPOTTING) FOR A SHERIFF'S DEPT, I WAS REQUESTED BY THE SPOTTER, A DEPUTY SHERIFF, TO SET DOWN IN A FIELD SO THAT HE COULD RELIEVE HIMSELF. AFTER LNDG, THE DEPUTY ASKED IF I NEEDED TO GO. I SAID NO, HE ASKED IF I WAS SURE, I RECONSIDERED AND SAID YES. WHILE THE DEPUTY WAS EXITING THE ACFT I LOCKED DOWN THE CTL FRICTION LOCKS FOR THE CYCLIC AND COLLECTIVE, TURNED OFF THE GOVERNOR AND REDUCED RPM TO APPROX 80 PERCENT, AND ALSO EXITED THE ACFT. WHILE 'RELIEVING' OURSELVES NEXT TO THE ACFT THE DEPUTY WAS APPARENTLY STANDING ON THE SKID. HE SUDDENLY STATED, 'I JUST FELT THE SKID ROCK UP UNDER MY FOOT.' I TURNED TO THE ACFT TO SEE THE DEPUTY ALSO FACING IT AND STARTED TO ENTER THE ACFT. BEFORE I COULD ENTER THE ACFT ROCKED BACKWARDS BRINGING THE NOSE A SUBSTANTIAL DISTANCE UP OFF OF THE GND. THE ENG RPM INCREASED SUBSTANTIALLY (BY THE NOISE LEVEL). THE ACFT LIFTED OFF THE GND, ROLLED L AND CAME TO REST ON ITS L SIDE WITH SUDDEN ENG STOPPAGE. IN THE SEQUENCE OF EVENTS, THE TAIL ROTOR ALSO STRUCK THE GND. I WAS PUSHED FORWARD AND AWAY FROM THE ACFT AND THE DEPUTY WAS PUSHED TO THE SIDE, AWAY FROM THE ACFT, BY THE SKID HE WAS STANDING ON. NO INJURIES RESULTED. I FEEL THAT CONTRIBUTING FACTORS WERE STRONG GUSTY WIND CONDITIONS THROUGH THE VALLEY IN WHICH THE INCIDENT TOOK PLACE. I CAN NOT EXPLAIN THE INCREASE IN RPM THAT APPARENTLY CAUSED THE ACFT TO 'LIFT OFF' ALTHOUGH I THEORIZE THAT THE ACFT TAIL ROTOR WAS TAKEN OFF BY GND CONTACT WHICH SUPPLIED INCREASED PWR TO THE MAIN ROTOR. I ALSO REALIZE THAT THE CTL FRICTION ON THIS HELI IS PROBABLY NOT ADEQUATE TO HOLD CTL SURFACES IN POS IN THE ABSENCE OF THE PLT, AND I SHOULD NOT HAVE LEFT THE ACFT WHILE IT WAS RUNNING.

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.