History of Flight
On March 28, 2013, at approximately 1119 mountain standard time, a Mooney M20A, registration N6018X, conducted an off-airport forced landing near Wikieup, Arizona. The pilot, who was the owner, operated the aircraft under 14 CFR Part 91. The private pilot and one passenger sustained serious injuries; another passenger, seated in the back, sustained fatal injuries. The airplane incurred substantial damage from impact forces.
The cross-country personal flight departed from Sedona, Arizona, and was destined for Shafter, California. Visual meteorological conditions prevailed, and no flight plan had been filed.
Communications with Albuquerque Air Route Traffic Control Center began at 1028:07, when the pilot requested VFR flight following. At 1106:01, the pilot reported a loss of engine oil pressure and requested vectors to the nearest airport. The controller provided vectors to Bagdad Airport. At 1109:30, the pilot reported altitude loss, and a nearby aircraft was asked to assist. At 1113:28, the accident airplane was 5 miles from Bagdad at 6,600 feet. At 1115:56, the pilot reported the engine running rough, then smoke in the cockpit, and he shut the engine off. The controller advised the pilot to look for an open field, clean up the airplane, and shut off the fuel. The pilot indicated he saw an open area. The last transmission from the pilot was at 1118:07.
The pilot executed a forced landing in rough terrain. The pilot and front-seat passenger were pinned in the wreckage; the rear-seat passenger, the pilot's son who sustained serious injury, was able to egress.
A witness camping about 1 mile away observed the airplane flying 300-400 feet overhead, with wings rocking. The witness stated the engine was silent, the landing gear was down, and no smoke or fluids were seen.
Aircraft Information
The aircraft was a Mooney M20A, serial number 1606. Total airframe time at the last annual inspection on October 3, 2012, was 3,761.8 hours. The tachometer read 1,048.8 hours at that inspection and 1,064.37 hours at the accident scene. The airplane was not equipped with shoulder harnesses.
The engine was a 180-horsepower Lycoming O-360-A1D, serial number L-9731-36A. Total engine time at the last annual inspection was 3,739.6 hours, with time since major overhaul of 1,179.8 hours.
Wreckage and Impact Information
The wreckage came to rest upright on mountainous terrain along a descending ridge. The first identified point of contact was an ocotillo cactus with broken branches. A ground scar and a piece of leading edge from the left wing were found. The principal impact crater was about 5 feet wide and 10 feet long. The main wreckage was 60 feet from the first point of contact. The pilot's window was found 65 feet away.
Black viscous fluid was observed on the belly of the fuselage. The belly was crushed upward and aft. The nose gear was crushed upward. The Johnson bar landing gear handle was in the vertical position. The ignition switch was off.
Tests and Research
Examination of the engine revealed the crankshaft would not rotate. A non-Lycoming shim of varying thickness was found between the propeller hub and the crankshaft flange; its origin could not be determined. Magnetos produced spark. A fracture was found on the crankcase at the number two cylinder area.
No oil registered on the dipstick, and the oil filter contained magnetic and bronze material. The oil sump held about 1/2 quart of black, burnt fluid with debris, including parts of the number two connecting rod. The oil suction screen was obscured with magnetic material.
Disassembly showed the crankcase halves had a substance consistent with automotive gasket sealer. The number two connecting rod had fractured and separated. The crankshaft journal for rod number two was thermally damaged and scored. Rod number three was thermally seized. The crankshaft flange was out of round by about 0.87 inch, far exceeding manufacturer limits.
Materials laboratory examination of the crankshaft and shim showed the propeller flange was tilted 0.726 degrees relative to the main journal axis, causing displacement up to 0.038 inch at the outer edge. The shim thickness varied from 0.0035 to 0.0884 inch.
Maintenance History
Logbook entries showed a propeller strike inspection in November 2006, a gear-up landing repair in March 2007, and replacement of the original engine with the accident engine in December 2008. The accident pilot purchased the airplane in January 2011. Subsequent annual and 100-hour inspections were recorded, but no logbook entry documented the installation or origin of the nonstandard shim.