NYC04LA118 · Cessna T-50

The pilot/mechanic purchased the floatplane about 7 months prior to the accident, and performed his own maintenance. When the airplane was de-fueled and lifted by crane onto the bay, the weight was calculated as 5,790 lbs. The certificated maximum gross takeoff weight of the airplane was 5,700 lbs. On the day prior to the accident, during high-speed taxis, the left engine only developed partial power. The pilot had the spark plugs cleaned and gapped. That evening, he was able to complete a short flight, in ground effect over the water. On the day of the accident, the airplane completed two high-speed taxis or attempted takeoffs, but did not become airborne. On the third attempt, the airplane traveled 3,000 to 4,000 feet on the water, before becoming airborne, and barely cleared a 20-foot-tall building by about 10 feet. Subsequently, witnesses near the accident site heard banging, sputtering, engine misfires, and popping, before the airplane struck trees near a lake. Examination of the wreckage revealed that the left propeller was in the feather position, and the right propeller blades were bent aft, with little to no rotational damage noted. However, the left mixture, propeller control, and throttle control were in the full forward position. The right throttle control was about 3/4 closed, the right propeller control was in the feather position, and the right mixture was full forward. Further inspection revealed that both fuel tanks contained adequate fuel. The aircraft logbooks were not recovered, and the date of the last annual inspection was unknown. Prior to having the airplane lifted onto the bay, the date of the last successful flight was also unknown.

Verbatim NTSB analysis and probable cause from the NTSB dataset