On January 27, 1998, at 1150 eastern standard time, a Kaman K-1200, N135KA, was substantially damaged when it collided with the ground during a hovering autorotation at the Kaman Aerospace plant, Bloomfield, Connecticut. The certificated airline transport pilot was not injured. Visual meteorological conditions prevailed and a flight plan was not filed. The flight was conducted under 14 CFR Part 91, and originated at Bloomfield, Connecticut. The pilot, a Federal Aviation Administration (FAA) Safety Inspector from the Southwest Regional Rotorcraft Certification Office, said that this was a familiarization flight. He said on his first flight, he practiced takeoffs, landings, hovering, and two hovering autorotations successfully. He said that he had to discontinue his maneuvers in the traffic pattern due to another airplane in the pattern, so he requested to use the pad near the plant. During a hovering autorotation maneuver from 5 feet AGL, the helicopter drifted to the left. Despite his efforts of correcting with right cyclic, the helicopter touched down on the left main landing gear, followed by the nosewheel, rolled over, and came to rest on its left side. According to the pilot, the helicopter had accumulated over 12 flight hours, and he had over 9 hours of total flight experience in make and model. According to an FAA Inspector from the Windsor Locks Flight Standards District Office, examination of the wreckage did not disclose any evidence of mechanical malfunction with the helicopter or engine, and the pilot did not report any.