LAX02LA189

The helicopter landed hard during an autorotation following the failure of one clutch drive belt. While maneuvering about 500 feet above ground level during an aerial photography business-related flight, the pilot and passenger smelled an unusual odor. About 5 seconds later, the pilot felt a jolt and observed the "Clutch Light" illuminate in the cockpit. The pilot initiated an autorotative descent but misjudged his landing flare, and the helicopter touched down hard on the underlying level open terrain. During the event, the clutch light illuminated continuously. The pilot did not follow the prescribed flight manual emergency procedure to pull the clutch circuit breaker. Engine power was not lost. The pilot allowed rotor rpm to decrease, and he erroneously entered an autorotation rather than performing the prescribed immediate landing while being prepared for the possibility of an autorotative descent. The subsequent wreckage examination revealed one of the two rotor system drive (vee) belts had broken. The second belt was intact, with the lower section of the belt found on the lower pulley in the correct position. The upper section of the belt on the upper pulley was found shifted forward one groove on the pulley.

On June 08, 2002 about 0720 Pacific daylight time, a Robinson R22 Beta, N7176S, made a forced landing and touched down hard on level, open dirt terrain, about 3 miles north-northeast of Henderson, Nevada. The helicopter was substantially damaged. The commercial pilot and the passenger/photographer were not injured. The helicopter was operated by Silver State Helicopters, LLC, located in North Las Vegas, Nevada. The pilot was operating the helicopter under the provisions of 14 CFR Part 91 during the business flight. Visual meteorological conditions prevailed, and no flight plan had been filed. The flight originated from North Las Vegas about 0635.

The pilot reported to the National Transportation Safety Board investigator that, in part, the purpose of the flight was to obtain photographs of his various construction sites. A few minutes before the accident, the pilot landed at the Henderson Executive Airport, Nevada. He then took off, and while maneuvering in the area, he and his passenger smelled the odor of burnt rubber. About 5 seconds later, he felt a jolt and observed the "Clutch Light" illuminate in the cockpit. The main rotor speed (rpm) decreased from 104 to 97 percent. The helicopter was at an altitude of 500 feet above the ground. The pilot further reported that he initiated an autorotative descent, flared about 5 feet above the ground, and touched down hard. The helicopter remained upright during the landing, but the main rotor struck the tail boom and the landing skids spread apart. During the event, the clutch light stayed on continuously. The pilot did not indicate that during the mishap he took any action to pull the clutch circuit breaker.

Federal Aviation Administration (FAA) personnel inspected the helicopter. In pertinent part, the FAA personnel reported that one of the two installed vee-belts was found broken. The second belt was intact, with the lower section of the belt found on the lower pulley in the correct position. The upper section of the belt on the upper pulley was found shifted forward one groove on the pulley.

Regarding the clutch light, the following note and procedure are written in the "Emergency Procedures" section in the helicopter's FAA approved flight manual: "The clutch light may come on momentarily...during flight to retension the belts as they warm-up and stretch slightly. This is normal. If, however, the light flickers or comes on in flight and does not go out within 7 or 8 seconds, pull the CLUTCH circuit breaker, reduce power, and land immediately. Be prepared to enter autorotation."