At about 08:41 EST, a Robinson R22 crashed while conducting a 180 autorotation with turn to runway 10 at Pompano Beach Airpark. The helicopter was destroyed and the pilot and flight instructor sustained serious injuries. The flight originated about 3 minutes before the accident Two witnesses who are Robinson R22 instructor pilots stated they observed the helicopter in right closed traffic for runway 10. They observed the helicopter conduct a 180-degree autorotation before the accident, which resulted in a termination with power to the numbers on runway 10. They described the autorotation as poor. They decided to watch the helicopter since it remained in right closed traffic. The helicopter was at about 500 feet when it was observed to enter another autorotation with turn. Instead of turning to the right the helicopter turned to the left about 25 to 30 degrees, and it did not appear to be in trim. The helicopter was observed to start a flare below 50 feet, and the skids started to level. The helicopter continued forward and collided with the ground hard in a nose low attitude, and rolled forward end over end before coming to a complete stop.