19980926037629A

(.19)On September 26, 1998, at 1100 hours pacific daylight time, a Texas helicopter corporation OH-13H, N1001G, crashed in a field near Gilroy, California. The aircraft was destroyed and the commercial pilot, the sole occupant, was not injured. The flight was conducted under the provisions of 14 CFR 137 as an aerial application flight, and originated at the hollister, California, airport, about 0700. Visual meteorological conditions prevailed and no flight plan was filed. The pilot reported that he had finished spraying the field and was headed back to the airport, approximately 50 feet AGL, when he felt a strong vibration throughout the entire helicopter. The aircraft pitched up and gained about 50 to 75 feet of altitude and began to turn to the right. The pilot reported that he lowered the collective, input full left cyclic, and leveled the helicopter. He stated that the helicopter was then flying approxiamtely 90 degrees to the original direction of flight, and, about 15 feet AGL, he lost control and the helicopter impacted the ground in a 30 to 45 degree left roll attitude. The pilot stated that the engine still running for about 5 to 10 seconds after impact, then quit on its own. He reported that he had not experienced any malfunction with the aircraft prior to the accident. The operator did no report the accident until September 28, 1998. (-23) the aircraft took off from a loading area on a dirt road near a farm to go back to the airport. At approximately 200 yards from the depature point at an altitude of approximately 80 feet, the pilot stated that the Bell wasp OH13H/M74A, N1001G, that he was operating performed an uncommanded violent pitch up altitude maneuver. He stated, he immediately lowered the collective while experiencing extreme vibration before he lost control and crashed in a farm field on September 26, 1998, at approximately 1100 hours pacific daylight time. The pilot escaped uninjured.