Narrative:

During a normal tour flight from waimea-kohala airport in a helicopter with 4 passenger being 250 pounds below maximum gross weight. This flight was to the kohala mountain valleys. I departed the airport (2671 ft MSL) and started climbing toward the mountains, at 3400 ft MSL and 100 AGL I started a slow deceleration from 80 KTS with the intent to come to a hover and look down a valley to see if the WX was good enough for me to descend into the valley. Because sometimes low clouds fill the valley and all the surrounding areas are VFR. Well, as I was decelerating I could clearly see that I could not descend into the valley. So I started a left 180 degree turn at about 100 ft AGL. At this time I was at about 15-20 KTS. Sometimes in the mountains it's hard to tell wind direction, but I must have caught a tailwind from the ridgeline and the aircraft started settling with power. With not enough altitude to fly out of this condition, I just held maximum power and a level attitude with the hope that the impact would be minimal. But at about 3 ft AGL the aircraft started an uncontrolled rotation to the right. I concentrated on keeping the aircraft in a level attitude. We must have rotated 3 or 4 complete 360 degrees. We remained between 5-10 ft above the ground. I tried a number of things to stop the rotation. Finally I decided to lower the collective slightly and try to get the aircraft on the ground. We hit the ground while still rotating, but I think by lowering the collective the rotation slowed considerably. It was kind of a hard landing, but not much harder than a hovering automatic rotation. The area we landed in had some fairly tall ferns, but luckily the aircraft was still upright and everything seemed to be ok with no damage. So I picked the aircraft up to hover and everything still seemed ok so I apologized to my passengers and continued the tour. (This was my big mistake). After the completion of the tour and returning to our hangar and shutting the helicopter down, considerable damage was found to the tail rotor blades and the main rotor blades had slight dings in 2 of them. So, here's the moral of the story in my opinion. Never, never, never after an incident like that continue a flight. Shut down and get help. Something could have really let loose when that flight was continued. Also, about getting in a situation to induce loss of tail rotor effectiveness or settling with power. This was completely my fault, even though I have made a turn similar to that and under those same conditions. We as pilots need to be aware of all conditions around us and never get complacent.

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Original NASA ASRS Text

Title: HELI TOUR ACFT AT 100 FT AGL TURNING AWAY FROM MOUNTAINS AT SLOW SPD ENCOUNTERS TAILWIND AND SETTLES. ACFT ROTATES ABOUT 3 TIMES AND HITS GND.

Narrative: DURING A NORMAL TOUR FLT FROM WAIMEA-KOHALA ARPT IN A HELI WITH 4 PAX BEING 250 POUNDS BELOW MAX GROSS WT. THIS FLT WAS TO THE KOHALA MOUNTAIN VALLEYS. I DEPARTED THE ARPT (2671 FT MSL) AND STARTED CLBING TOWARD THE MOUNTAINS, AT 3400 FT MSL AND 100 AGL I STARTED A SLOW DECELERATION FROM 80 KTS WITH THE INTENT TO COME TO A HOVER AND LOOK DOWN A VALLEY TO SEE IF THE WX WAS GOOD ENOUGH FOR ME TO DSND INTO THE VALLEY. BECAUSE SOMETIMES LOW CLOUDS FILL THE VALLEY AND ALL THE SURROUNDING AREAS ARE VFR. WELL, AS I WAS DECELERATING I COULD CLRLY SEE THAT I COULD NOT DSND INTO THE VALLEY. SO I STARTED A L 180 DEG TURN AT ABOUT 100 FT AGL. AT THIS TIME I WAS AT ABOUT 15-20 KTS. SOMETIMES IN THE MOUNTAINS IT'S HARD TO TELL WIND DIRECTION, BUT I MUST HAVE CAUGHT A TAILWIND FROM THE RIDGELINE AND THE ACFT STARTED SETTLING WITH PWR. WITH NOT ENOUGH ALT TO FLY OUT OF THIS CONDITION, I JUST HELD MAX PWR AND A LEVEL ATTITUDE WITH THE HOPE THAT THE IMPACT WOULD BE MINIMAL. BUT AT ABOUT 3 FT AGL THE ACFT STARTED AN UNCTLED ROTATION TO THE R. I CONCENTRATED ON KEEPING THE ACFT IN A LEVEL ATTITUDE. WE MUST HAVE ROTATED 3 OR 4 COMPLETE 360 DEGS. WE REMAINED BTWN 5-10 FT ABOVE THE GND. I TRIED A NUMBER OF THINGS TO STOP THE ROTATION. FINALLY I DECIDED TO LOWER THE COLLECTIVE SLIGHTLY AND TRY TO GET THE ACFT ON THE GND. WE HIT THE GND WHILE STILL ROTATING, BUT I THINK BY LOWERING THE COLLECTIVE THE ROTATION SLOWED CONSIDERABLY. IT WAS KIND OF A HARD LNDG, BUT NOT MUCH HARDER THAN A HOVERING AUTO ROTATION. THE AREA WE LANDED IN HAD SOME FAIRLY TALL FERNS, BUT LUCKILY THE ACFT WAS STILL UPRIGHT AND EVERYTHING SEEMED TO BE OK WITH NO DAMAGE. SO I PICKED THE ACFT UP TO HOVER AND EVERYTHING STILL SEEMED OK SO I APOLOGIZED TO MY PAXS AND CONTINUED THE TOUR. (THIS WAS MY BIG MISTAKE). AFTER THE COMPLETION OF THE TOUR AND RETURNING TO OUR HANGAR AND SHUTTING THE HELI DOWN, CONSIDERABLE DAMAGE WAS FOUND TO THE TAIL ROTOR BLADES AND THE MAIN ROTOR BLADES HAD SLIGHT DINGS IN 2 OF THEM. SO, HERE'S THE MORAL OF THE STORY IN MY OPINION. NEVER, NEVER, NEVER AFTER AN INCIDENT LIKE THAT CONTINUE A FLT. SHUT DOWN AND GET HELP. SOMETHING COULD HAVE REALLY LET LOOSE WHEN THAT FLT WAS CONTINUED. ALSO, ABOUT GETTING IN A SITUATION TO INDUCE LOSS OF TAIL ROTOR EFFECTIVENESS OR SETTLING WITH PWR. THIS WAS COMPLETELY MY FAULT, EVEN THOUGH I HAVE MADE A TURN SIMILAR TO THAT AND UNDER THOSE SAME CONDITIONS. WE AS PLTS NEED TO BE AWARE OF ALL CONDITIONS AROUND US AND NEVER GET COMPLACENT.

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.