ANC83FA064

Witnesses reported that after takeoff, the plt flew by a cabin at approximately 200 ft, signaled by rocking the acft's wings, then began a gradual climb. The climb increased in steepness until 1 witness could see the entire top of the acft. It then nosed over, made 1 1/2 to 2 1/2 turns & crashed. An investigation revealed no specific preimpact malfunction or failure. However, an investigation revealed that acft had received 3 major modifications, 2 of which were under supplemental type certificates (stc's). A modified elevator bellcrank had been installed, but there was no floor or protective covering installed over the bellcrank. Only a canvas barrier protected the bellcrank from items placed in the baggage compartment. The edges of the canvas did not extend to the sides, top & bottom of the fuselage, but instead, there was a 2 to 3 inch cap, laced withe string to hold the canvas secure. A whisk broom was found in the proximity of the elevator bellcrank.