20010518020349A

(.19) On may 18, 2001, at 0940 central daylight time, a Eurocopter AS-350-B2 helicopter, N311TV, was substantially damaged during an approach when it impacted the helipad on the channel 11 television building in Houston, Texas. The helicopter was registered to and operated by U.S. Helicopters inc., of marshville, north carolina. The commercial pilot, sole occupant of the helicopter, sustained minor injuries. Visual meteorological conditions prevailed and no flight plan was filed for the 14 code of federal regulations part 91 business flight. The local flight originated from the channel 11 helipad. According to the pilot, he was making an approach to the helipad, and was 15-20 feet above the helipad, when the helicopter experienced a "hydraulic failure." He stated that the hydraulic warning light on the caution panel illuminated; however, the warning horn did not activate. Subsequently, the helicopter impacted the helipad with the right skid, rolled over to the right, and came to rest on its right side. According to the FAA inspectors and a representative from American Eurocopter, who examined the helicopter and the accident site, the main rotor blades were damaged. The engine mou nts and the skids sustained damage, and the tail rotor drive shaft separated. (-23) on may 18, 2001, at 0940 central daylight time, a Eurocopter AS-350-B2 helicopter, N311TV, was substantially damaged during an approach when it impacted the heli-pad on the channel 11 television building in Houston, Texas. The helicopter was registered to and operated by U.S. Helicopters inc., of marshville, north carolina. The commercial pilot, sole occupant of the helicopter, sustained minor injuries. Visual meteorological conditions prevailed and no flight plan was filed for the 14 code of federal regulation part 91 business flight. The local flight originated from the channel 11 heli-pad. According to the pilot he was making an approach to the heli-pad, and was 15-20 feet above the helepad, when the helicopter experienced a "hydraulic failure." He stated that the hydraulic warning light on the caution panel illuminated; however, the warning horn did not activate. Subsequently, the helicopter impacted the heli-pad with the right skid, rolled over to the right, and came to a rest on its right side. The main rotor blades was de stroyed, engine mounts and the skids sustained damage, and the tail rotor shaft separated. (.4) the helicopter was on final approach, approximately 15 feet above the roof top helipad, when the helicopter's controls "became very stiff." The pilot observed the "hyd" light on the caution panel illuminated; however, the audible hydraulic warning horn did not activate. Subsequently, the helicopter impacted the helipad with the right skid, and rolled onto its right side. Examination of the helicopter's cockpit revealed that the hydraulic cut-off switch, which is located on the collective control, was found in the cut-off position and its red plastic guard was broken (when the switch is in the cut-off position the hydraulic warning horn will not sound). The cockpit was examined for shattered pieces of the guard; however, none were found. The hydraulic system was examined and no leaks were noted. A functional test of the hydraulic pump and regulator/manifold revealed no anomalies with either unit.