Incident Overview
The pilot of a general aviation aircraft reported that the airplane flew well but exhibited a poor rate of climb. Throughout the day, the pilot and his father, a CFI-rated passenger, had been practicing touch-and-go landings and repeatedly experienced difficulty achieving pattern altitude.
Preflight and Takeoff
After refueling the airplane and taking a short break, another flight was planned. According to the pilot, the preflight inspection and engine runup did not reveal any malfunctions. Due to the earlier lack of climb performance, the pilot used ten degrees of flaps during takeoff to improve lift.
Climb and Evasive Maneuver
The initial climb was uneventful. However, as the aircraft climbed through 100 feet above ground level, it appeared that the climb rate flattened. The pilot realized that they would not clear power lines located off the departure end of the runway. In an attempt to avoid the power lines, the pilot initiated a left turn, during which the aircraft collided with trees.