19990611006859A

Acft crashed on take-off and sustained substantial damage, other circumstances are unknown. (From .19) on June 11, 1999, about 1530 Alaska daylight time, a short takeoff and landing (stol) equipped Piper PA-18 airplane, N2668P, sustained substantial damage during takeoff at the Goose Bay airstrip, about 10 miles south of big lake, Alaska. The airplane was being operated as a visual flight rules (VFR) personal flight under title 14, CFR part 91, when the accident occurred. The certificated private pilot, the sole occupant, sustained serious injuries. Visual meteorological conditions prevailed, and no flight plan was filed. The flight was en route to merrill field, anchorage, Alaska. During a telephone conversation with the national transportation safety board (NTSB) investigator-in-charge (iic), on may 11, the pilot reported that he departed on runway 07. During the initial climb, about 100 feet above the ground, he said he encountered turbulence and windshear, and the airplane abruptly rolled to the right. He said he responded with abrupt aileron control input to the left, but the airplane did not respond. He indicated the controls felt "mushy, and ineffective." He was un able to regain control of the airplane, and it nosed down and collided with trees. The iic interviewed another pilot who departed the same runway 15 minutes prior to the accident airplane. This pilot reported moderate low level turbulence on initial climb. When he returned about 45 minutes later (about 30 minutes after the accident flight), he said the level of turbulence had increased, and he was forced to use full aileron control deflection during the approach and landing. An FAA airworthiness inspector went to the accident site the day of the accident and inspected the airplane. He reported to the NTSB iic that all the flight controls were attached to their appropriate controls, and appeared functional. He discovered no evidence of any preimpact mechanical anomaly. The airplane sustained substantial damage to the propeller and left wing. (-23) the aircraft departed runway 07. During the climb the aircraft encountered a strong wind which caused it to turn 90 degrees to the right. The pilot attempted to compensate without any effect from the flight controls, the pilot reduced power as the aircraft struck the ground and received substa ntial damage. An on scene investigation by an airworthiness inspector of the aircraft's flight controls did not reveal any problems. Other pilots who previously departed this area experienced a wind shear condition that did not cause them any problems. (.4) the pilot was departing a gravel airstrip bordered by trees in his short takeoff and landing (stol) equipped airplane. About 100 feet above the ground, he reported he encountered turbulence, and lost control of the airplane. The airplane collided with trees near the airstrip. Postaccident inspection of the airplane disclosed no evidence of any preimpact mechanical anomalies.