19980206002389A

Aircraft climbed to 150 ft AGL on takeoff. Banked into steep turn and dove into snow covered ground. (.4)the certificated commercial pilot was departing on a 14 CFR 135 cargo flight. The airplane lifted off and climbed to about 200 feet. Instead of turning right toward the intended destination, the airplane began a left turn toward the runway. The angle of bank increased to about 45 degrees. The airplane then nosed down, and descended into snow covered terrain, about 200 yards north of the runway. Examination of the engine revaled the number six sylinder head was fractured, and slightly separated from the sylinder barrel. The area around the point of separation was blackened and oily. Wimilar discoloration was noted on the inside of the engine cowl. A metallurgical examination of the cylinder head revealed a fatigue fracture along a large segment of the thread root radius between the 5th and 6th threads. The engine's cylinder compression is part of the operator's approved airworthiness inspection program. The number six sylinder compression, recorded 121 hours before the accident, was noted as 60 PSI. The last engine inspection, 27 hours before the accident, did not in clude a record of the engine compression. (-23) no narrative.