What happened
The incident began when the pilot observed that the battery power was insufficient for normal engine operation. In response, he elected to manually prime the engine using the hand-prime method. At the time of this procedure, the aircraft was not secured with wheel chocks or tied down to any fixed structure.
Critically, the magneto switch had been inadvertently left in the on position prior to the priming attempt. When the pilot engaged the starter, the engine ignited immediately without anyone inside the cabin. The sudden start caused the aircraft to begin moving forward, effectively taxiing on its own power.
The uncontrolled aircraft accelerated across the ramp area and collided with a parked airplane. It did not stop after the initial impact but continued its forward momentum until it finally struck the airport's windsock, bringing the movement to an end.