HISTORY OF FLIGHT On June 5, 2004, about 1550 mountain standard time, a Beech S35, N6127Q, impacted a guard rail during an emergency landing on a road, after a total loss of engine power, near Flagstaff, Arizona. The owner/pilot was operating the airplane under the provisions of 14 CFR Part 91. The private pilot and two passengers were not injured; the airplane sustained substantial damage. The cross-country personal flight departed Monument Valley Airport, Monument Valley, Utah, about 1515. Visual meteorological conditions prevailed. No flight plan had been filed. The primary wreckage was at 35 degrees 14.20 minutes north latitude and 111 degrees 28.55 minutes west longitude. The pilot submitted a Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2). The pilot reported that while in cruise flight he observed a decrease in the engine manifold pressure. He adjusted the throttle to increase the manifold pressure, but the pressure continued to drop. He observed that the oil pressure was also low. The pilot declared an emergency and attempted to land at Flagstaff Pulliam Airport. About 13 miles northeast of Flagstaff, the engine lost all power and the pilot performed a forced landing on Townsend Winona Highway. During the landing roll the right wingtip contacted a highway guardrail, and subsequently the right wing was detached from the airplane. The airplane was recovered for further examination. TESTS AND RESEARCH On August 3, 2004, the engine was removed from the airplane to determine the cause of the oil leak. It was determined that the turbocharger oil drain line fitting gasket and o-ring was brittle and broken. The oil was leaking onto the top of the exhaust pipe and flowing down the belly of the airplane. ADDITIONAL INFORMATION The National Transporation Safety Board investigator-in-charge released the wreckage to the owner's representative.