On September 30, 1998, at 1130 hours Pacific daylight time, a Robinson R22B, N8340D, crashed in a practice area north of Salinas, California. The aircraft was destroyed, and the private airplane rated pilot, the sole occupant, suffered serious injuries. The flight originated at the Salinas Airport at 1030, and no flight plan was filed. Visual meteorological conditions prevailed. The chief pilot of the flight school reported that the student helicopter pilot was briefed for his first nonsupervised solo flight. The pilot was told to practice traffic patterns, and was instructed to only fly normal approaches and takeoffs, with no emergency maneuvers. The student pilot reported that he worked on normal traffic patterns, then decided to practice autorotations to a go-around. He entered the autorotation from approximately 800 feet agl and 70 knots of airspeed. He stated that he initiated the autorotation by cutting the throttle and lowering the collective. He then turned 180 degrees to position the aircraft into the wind. The pilot reported that he noticed the rotor rpm rising rapidly so he raised the collective and applied aft cyclic to slow the airspeed to 65 knots. Approximately 200 to 300 feet agl, he initiated a go-around to abort the autorotation. The pilot stated that he raised the collective to add power but didn't get the response he was looking for. He stated that at that point he was "not sure what was going wrong but felt [he] was losing control and going down very fast." He further stated that "all inputs of raising the collective weren't slowing [him] down at all." The pilot reported that once he realized he was about to hit the ground, he pulled up on the collective and applied full aft cyclic. The helicopter impacted the ground and rolled over. The chief pilot reported that when the pilot called him for help after the accident, the pilot stated, "I did what you told me not to do." The student pilot had been given a solo endorsement on September 14, 1998.