N976HB

The pilot connected his car battery to the airplane's battery with jumper cables and started the airplane's engine. He stated that the airplane's wheels were not chocked, the parking brake was not set, and as he detached the jumper cables from the airplane's battery, the airplane "started to taxi." The pilot stopped the airplane by holding on to the wing strut, and instructed the passenger inside the airplane to step on the toe brakes. During his second attempt to detach the jumper cables, the airplane moved forward again. According to the pilot, "I ran around again to stop the plane [and] I ran into the prop…" The pilot sustained a serious injury to his left arm.