During a local sightseeing flight, the pilot descended through an altitude of 1,000 feet to be able to see a waterway below him. As the pilot performed the low flight maneuver, the airplane impacted a power line, causing the vertical stabilizer to separate from the airplane. The pilot reported experiencing resistance and a vibration with the airplane, followed by a loss of control. He was able to subsequently perform a forced landing straight ahead, during which the airplane sustained damage to the nose gear and to the rudder. A witness stated that he heard a low flying airplane, followed by a loud noise similar to a "pop," and then he observed the airplane dragging a cable. Examination of the accident site by a Federal Aviation Administration inspector revealed the vertical stabilizer, with 150 feet of power line still attached. It was located approximately 300 feet aft of the wreckage. No pre-impact malfunctions were reported by the pilot or identified during the post-accident examination.