What happened
Following refueling, the crew taxied to the east end of the lake for departure. The weather conditions at the time involved a west wind estimated at 12 knots. Prior to takeoff, the pilot completed all checklists and verified that the controls were tested, free, and correct.
As the floatplane reached flying speed of approximately 60 knots and transitioned onto the step, the right float was raised. Upon applying slight back pressure to become airborne, the pilot attempted to move the control wheel to the right to level the aircraft, but found the control wheel was jammed.
The pilot suspected that a passenger's knee was positioned beneath the right side of the control wheel, preventing it from returning to the neutral position. Despite the pilot instructing the passenger to move, the jam persisted. The aircraft entered an increasing left bank and began losing altitude despite the application of full power. Within 10 to 15 seconds of liftoff, the aircraft impacted the water in a left bank of approximately 40 degrees and a nose-down attitude of 45 degrees, completing a 180-degree turn from the original takeoff heading.
The accident resulted in one passenger sustaining serious injuries, while the pilot and one other passenger were uninjured.
A passenger on board noted hearing the pilot call out regarding their knee. While the passenger observed the left side of the control wheel against their left knee, they noted no visible obstruction to movement and observed no bruising or abrasions on their legs following the event.
The investigation
An FAA examination of the wreckage revealed no pre-impact anomalies in the aircraft's mechanical systems.