Narrative:

The incident began at hite marina airport on lake powell, ut. I was part of a group of 5 similar airplanes there to pick up a group of river rafters and take them back to canyonlands airport near moab, ut. The dividing up of the passenger to each of the planes was handled by the man in charge who also held the contract for this job. The load I was given was 5 men, 2 of them quite large, and quite a lot of baggage. There were no scales in the plane so there was no way to know exactly what the load was. However, it was clear that it came very close to maximum weight. I refused some of the bags and put them aboard another plane. I loaded up the passenger and proceeded to depart. The takeoff was normal and although I could feel the weight of the plane, it did climb out normally. The WX was hot with high winds and turbulence as is usual for this location. There were also updrafts and downdrafts. On climb out, I flew into one of these downdrafts and the plane began to sink. I was flying over the river, which had steep canyon walls. In this downdraft, I could not climb out of the canyon. I knew that eventually the downdraft would abate and I could climb out, but my passenger were beginning to panic. 2 of them were pilots themselves. The passenger sitting behind me took the initiative without my orders to open the pilot side door and throw out all the bags into the river below, a load of perhaps 150 pounds. I did not resist this move as to do so may have increased their panic. Eventually the downdraft abated and the plane climbed out of the canyon and up to a safe altitude, then landed safely at canyonlands. In retrospect, I believe there are a number of ways the incident could have been avoided. I could have been more conservative on the load and refused more bags. It was clear that the load was heavy. I had flown out of this same location with heavy loads and I was overconfident about the capabilities of the plane. Also, unconsciously, I was relying on the judgement of 2 of the other pilots present. 1 of the 2 was the man in charge of the operation. Both of these pilots had much more experience at this location than I did. I could also have been more cognizant of the WX conditions and could have allowed for the possibility of downdrafts.

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Original NASA ASRS Text

Title: A C206 DEPARTED UT03 AND BEGAN DSNDING OVER THE RIVER. THE DSCNT CAUSED 2 PAX PLTS TO START DISCARDING BAGGAGE UNTIL THE ACFT RESUMED CLBING.

Narrative: THE INCIDENT BEGAN AT HITE MARINA ARPT ON LAKE POWELL, UT. I WAS PART OF A GROUP OF 5 SIMILAR AIRPLANES THERE TO PICK UP A GROUP OF RIVER RAFTERS AND TAKE THEM BACK TO CANYONLANDS ARPT NEAR MOAB, UT. THE DIVIDING UP OF THE PAX TO EACH OF THE PLANES WAS HANDLED BY THE MAN IN CHARGE WHO ALSO HELD THE CONTRACT FOR THIS JOB. THE LOAD I WAS GIVEN WAS 5 MEN, 2 OF THEM QUITE LARGE, AND QUITE A LOT OF BAGGAGE. THERE WERE NO SCALES IN THE PLANE SO THERE WAS NO WAY TO KNOW EXACTLY WHAT THE LOAD WAS. HOWEVER, IT WAS CLR THAT IT CAME VERY CLOSE TO MAX WT. I REFUSED SOME OF THE BAGS AND PUT THEM ABOARD ANOTHER PLANE. I LOADED UP THE PAX AND PROCEEDED TO DEPART. THE TKOF WAS NORMAL AND ALTHOUGH I COULD FEEL THE WT OF THE PLANE, IT DID CLB OUT NORMALLY. THE WX WAS HOT WITH HIGH WINDS AND TURB AS IS USUAL FOR THIS LOCATION. THERE WERE ALSO UPDRAFTS AND DOWNDRAFTS. ON CLBOUT, I FLEW INTO ONE OF THESE DOWNDRAFTS AND THE PLANE BEGAN TO SINK. I WAS FLYING OVER THE RIVER, WHICH HAD STEEP CANYON WALLS. IN THIS DOWNDRAFT, I COULD NOT CLB OUT OF THE CANYON. I KNEW THAT EVENTUALLY THE DOWNDRAFT WOULD ABATE AND I COULD CLB OUT, BUT MY PAX WERE BEGINNING TO PANIC. 2 OF THEM WERE PLTS THEMSELVES. THE PAX SITTING BEHIND ME TOOK THE INITIATIVE WITHOUT MY ORDERS TO OPEN THE PLT SIDE DOOR AND THROW OUT ALL THE BAGS INTO THE RIVER BELOW, A LOAD OF PERHAPS 150 LBS. I DID NOT RESIST THIS MOVE AS TO DO SO MAY HAVE INCREASED THEIR PANIC. EVENTUALLY THE DOWNDRAFT ABATED AND THE PLANE CLBED OUT OF THE CANYON AND UP TO A SAFE ALT, THEN LANDED SAFELY AT CANYONLANDS. IN RETROSPECT, I BELIEVE THERE ARE A NUMBER OF WAYS THE INCIDENT COULD HAVE BEEN AVOIDED. I COULD HAVE BEEN MORE CONSERVATIVE ON THE LOAD AND REFUSED MORE BAGS. IT WAS CLR THAT THE LOAD WAS HVY. I HAD FLOWN OUT OF THIS SAME LOCATION WITH HVY LOADS AND I WAS OVERCONFIDENT ABOUT THE CAPABILITIES OF THE PLANE. ALSO, UNCONSCIOUSLY, I WAS RELYING ON THE JUDGEMENT OF 2 OF THE OTHER PLTS PRESENT. 1 OF THE 2 WAS THE MAN IN CHARGE OF THE OP. BOTH OF THESE PLTS HAD MUCH MORE EXPERIENCE AT THIS LOCATION THAN I DID. I COULD ALSO HAVE BEEN MORE COGNIZANT OF THE WX CONDITIONS AND COULD HAVE ALLOWED FOR THE POSSIBILITY OF DOWNDRAFTS.

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.