Narrative:

On departure from the steinhatchee river the aircraft came within 10 or 20 ft of impacting trees. I had flown the aircraft into the river location on the previous day. In observing the area before landing there appeared to be more than sufficient area for a normal landing and departure. Landing was uneventful. Later the same day I departed for a short trip to obtain fuel. The aircraft was light and with a stiff breeze the departure was normal. I was, however, uncomfortable with the clearance of the aircraft over tall trees at a bend in the river. I decided at the time I would depart next time without my passenger and pick her up at a location without departure obstructions. The next morning was calm, clear, and cooler than the previous day. Because arrangements to take the passenger to another location would have inconvenienced our friends and delayed our departure, I decided to depart with both of us onboard. I taxied to the most upstream portion of the river. The aircraft seemed to operate normally but the takeoff run was longer than I expected. At the point of lift-off I still expected to have sufficient performance to clear the trees. The climb rate was extremely poor. I maintained 20 degrees of flaps for maximum climb rate. It quickly became obvious I would not clear the closest trees. I was able to bank sufficiently to follow the river and gain additional time for climbing. This required bank angles at low speed, close to the river. Ultimately the river course became impossible to follow and I had no choice but to try and clear the trees. The airplane had climbed sufficiently to clear the trees by about 10 ft to 20 ft. The remainder of the climb out was slow, but unremarkable. The kit built aircraft does not have an operating manual. It is a 2-PLACE amphibian with a listed maximum gross weight of 1175 pounds. Empty weight is 575 pounds, or 650 pounds with full fuel. A passenger represents a significant percentage of gross weight and greatly degrades aircraft performance. Based on other aircraft I have always assumed that 20 degrees of flap would give the best angle of climb. Typically, however, I use 20 degrees to get off the water and 10 degrees to climb. I'm not certain that 20 degrees provides the best performance under the circumstances. Contributing factors: 1) the airplane was at maximum gross weight, 2) the wind conditions were calm as compared to the previous day, 3) I did not want to delay the departure and encounter increased air temperatures, increased river activity, and inconvenience our friends, 4) failure to test the maximum climb performance of the aircraft in safer conditions, 5) an optimistic assessment of climb performance with 20 degrees of flaps at maximum gross weight, and 6) no clearly established go/no-go point. I've read many accident reports and thought I was not susceptible to the errors of judgement that could have resulted in an accident in this case. In retrospect I should have stuck with the decision to depart by myself at a low gross weight. An alternative would have been to taxi to a better departure area. I underestimated my susceptibility to external influences (friends, convenience). I overestimated the aircraft and pilot capabilities. As corrective action a checklist which includes consideration of the consequences of an erroneous estimate could make the more conservative decision easier. The aircraft performance will be checked under controled conditions and a safety factor applied for future operations.

Google
 

Original NASA ASRS Text

Title: PLT OF EXPERIMENTAL SEAPLANE BUCCANEER MAKES A TKOF AND BARELY CLBS ABOVE TREES.

Narrative: ON DEP FROM THE STEINHATCHEE RIVER THE ACFT CAME WITHIN 10 OR 20 FT OF IMPACTING TREES. I HAD FLOWN THE ACFT INTO THE RIVER LOCATION ON THE PREVIOUS DAY. IN OBSERVING THE AREA BEFORE LNDG THERE APPEARED TO BE MORE THAN SUFFICIENT AREA FOR A NORMAL LNDG AND DEP. LNDG WAS UNEVENTFUL. LATER THE SAME DAY I DEPARTED FOR A SHORT TRIP TO OBTAIN FUEL. THE ACFT WAS LIGHT AND WITH A STIFF BREEZE THE DEP WAS NORMAL. I WAS, HOWEVER, UNCOMFORTABLE WITH THE CLRNC OF THE ACFT OVER TALL TREES AT A BEND IN THE RIVER. I DECIDED AT THE TIME I WOULD DEPART NEXT TIME WITHOUT MY PAX AND PICK HER UP AT A LOCATION WITHOUT DEP OBSTRUCTIONS. THE NEXT MORNING WAS CALM, CLR, AND COOLER THAN THE PREVIOUS DAY. BECAUSE ARRANGEMENTS TO TAKE THE PAX TO ANOTHER LOCATION WOULD HAVE INCONVENIENCED OUR FRIENDS AND DELAYED OUR DEP, I DECIDED TO DEPART WITH BOTH OF US ONBOARD. I TAXIED TO THE MOST UPSTREAM PORTION OF THE RIVER. THE ACFT SEEMED TO OPERATE NORMALLY BUT THE TKOF RUN WAS LONGER THAN I EXPECTED. AT THE POINT OF LIFT-OFF I STILL EXPECTED TO HAVE SUFFICIENT PERFORMANCE TO CLR THE TREES. THE CLB RATE WAS EXTREMELY POOR. I MAINTAINED 20 DEGS OF FLAPS FOR MAX CLB RATE. IT QUICKLY BECAME OBVIOUS I WOULD NOT CLR THE CLOSEST TREES. I WAS ABLE TO BANK SUFFICIENTLY TO FOLLOW THE RIVER AND GAIN ADDITIONAL TIME FOR CLBING. THIS REQUIRED BANK ANGLES AT LOW SPD, CLOSE TO THE RIVER. ULTIMATELY THE RIVER COURSE BECAME IMPOSSIBLE TO FOLLOW AND I HAD NO CHOICE BUT TO TRY AND CLR THE TREES. THE AIRPLANE HAD CLBED SUFFICIENTLY TO CLR THE TREES BY ABOUT 10 FT TO 20 FT. THE REMAINDER OF THE CLBOUT WAS SLOW, BUT UNREMARKABLE. THE KIT BUILT ACFT DOES NOT HAVE AN OPERATING MANUAL. IT IS A 2-PLACE AMPHIBIAN WITH A LISTED MAX GROSS WT OF 1175 LBS. EMPTY WT IS 575 LBS, OR 650 LBS WITH FULL FUEL. A PAX REPRESENTS A SIGNIFICANT PERCENTAGE OF GROSS WT AND GREATLY DEGRADES ACFT PERFORMANCE. BASED ON OTHER ACFT I HAVE ALWAYS ASSUMED THAT 20 DEGS OF FLAP WOULD GIVE THE BEST ANGLE OF CLB. TYPICALLY, HOWEVER, I USE 20 DEGS TO GET OFF THE WATER AND 10 DEGS TO CLB. I'M NOT CERTAIN THAT 20 DEGS PROVIDES THE BEST PERFORMANCE UNDER THE CIRCUMSTANCES. CONTRIBUTING FACTORS: 1) THE AIRPLANE WAS AT MAX GROSS WT, 2) THE WIND CONDITIONS WERE CALM AS COMPARED TO THE PREVIOUS DAY, 3) I DID NOT WANT TO DELAY THE DEP AND ENCOUNTER INCREASED AIR TEMPS, INCREASED RIVER ACTIVITY, AND INCONVENIENCE OUR FRIENDS, 4) FAILURE TO TEST THE MAX CLB PERFORMANCE OF THE ACFT IN SAFER CONDITIONS, 5) AN OPTIMISTIC ASSESSMENT OF CLB PERFORMANCE WITH 20 DEGS OF FLAPS AT MAX GROSS WT, AND 6) NO CLRLY ESTABLISHED GO/NO-GO POINT. I'VE READ MANY ACCIDENT RPTS AND THOUGHT I WAS NOT SUSCEPTIBLE TO THE ERRORS OF JUDGEMENT THAT COULD HAVE RESULTED IN AN ACCIDENT IN THIS CASE. IN RETROSPECT I SHOULD HAVE STUCK WITH THE DECISION TO DEPART BY MYSELF AT A LOW GROSS WT. AN ALTERNATIVE WOULD HAVE BEEN TO TAXI TO A BETTER DEP AREA. I UNDERESTIMATED MY SUSCEPTIBILITY TO EXTERNAL INFLUENCES (FRIENDS, CONVENIENCE). I OVERESTIMATED THE ACFT AND PLT CAPABILITIES. AS CORRECTIVE ACTION A CHKLIST WHICH INCLUDES CONSIDERATION OF THE CONSEQUENCES OF AN ERRONEOUS ESTIMATE COULD MAKE THE MORE CONSERVATIVE DECISION EASIER. THE ACFT PERFORMANCE WILL BE CHKED UNDER CTLED CONDITIONS AND A SAFETY FACTOR APPLIED FOR FUTURE OPS.

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.