LAX07LA058

The pilot reported that while in cruise flight the airplane began to vibrate, which was followed by a loud "bang," and then a complete loss of engine power. He attempted to restart the engine, trimmed the airplane to attain best glide speed, and looked for a place to make an emergency landing. The touchdown was normal; however, on the landing rollout the nose landing gear collapsed and the airplane came to rest inverted. An inspection of the engine revealed that the number 3 cylinder connecting rod had broken at the crankshaft journal. Cracks in multiple locations were observed on the right side engine case. Various pieces from the engine were located in the oil sump, oil pump housing, and oil filter element. The number 3 connecting rod, piston, and cylinder were thermally discolored (black coloration). Complete teardown of the engine revealed that the crankshaft at the number 3 journal area exhibited signs of thermal discoloration and distortion. The other connecting rods and main bearings showed signs of adequate lubrication. There were no oil system related discrepancies noted. A review of the engine logbooks revealed normal routine maintenance, which included 50-hour oil changes and servicing.

On December 21, 2006, at 1055 mountain standard time, a Cessna 152, N5295B, experienced a complete loss of engine power during cruise and the pilot made a forced landing in an open farm field about 11 miles southwest of Chandler Airport (CHD), Chandler, Arizona. The airplane sustained substantial damage after the nose landing gear collapsed and the airplane came to rest inverted. PMC Aviation LLC., d.b.a. Sunbird Flight Services, operated the airplane as a rental flight under the provisions of 14 Code of Federal Regulations Part 91. The private pilot and one passenger were not injured. Visual meteorological conditions prevailed for the local area flight that was destined for Glendale Airport (GEU), Glendale, Arizona. The flight departed CHD about 1043, and no flight plan had been filed.

According to the pilot, the fuel tanks were topped off at CHD, with no discrepancies noted when he sumped the fuel tanks. After startup, he received the current Automatic Terminal Information Service (ATIS) information, and then contacted CHD tower personnel and received a clearance to taxi to runway 22R. The run up was normal, and no abnormal readings were observed from the oil pressure gauge. He reported that the takeoff roll and climb out were normal.

The pilot stated that they reached a cruise altitude of 2,500 feet and proceeded westbound towards GEU when the airplane started to vibrate and he thought he heard a loud "bang." The propeller then came to an immediate stop. The pilot stated that he attempted to restart the engine with no success, and then trimmed the airplane for best glide (60 knots). He then contacted CHD tower and reported a mayday along with his current position. The pilot then made a turn to the south toward farm fields and looked for a place to land. The touchdown was normal; however, during the landing rollout the nose landing gear collapsed and the airplane came to rest inverted.

In a subsequent interview with the pilot, he reported that he checked the fluid levels, which included the oil level via the dipstick. The pilot stated that he did not recall what the exact oil level was, but that it was far enough up on the dipstick that he was not concerned.

A Federal Aviation Administration (FAA) airworthiness inspector responded to the accident site. He noted oil on the ground of the airplane, but no oil staining on either the belly of the fuselage or along the empennage or tail sections. After the airplane was righted, the engine cowling was removed to visually inspect the engine. The FAA inspector noted that the engine case at the aft end of the number 3 cylinder had a large crack on it that started at the top of the case and continued to the bottom of the case.

The National Transportation Safety Board investigator-in-charge (IIC), and an FAA airworthiness inspector conducted an engine tear down inspection at Air Transport, Phoenix, Arizona, on December 31, 2006.

A visual inspection of the engine revealed that the right side of the engine had cracked in multiple places. Multiple pieces of the engine case were found in the oil pan, along with hardware assembly for the number 3 connecting rod.

The IIC made an unsuccessful attempt to rotate the engine via the propeller, and noted that the engine had seized. The top spark plugs were removed. According to the Champion Aviation Check-a-Plug chart AV-27, the spark plug electrodes appeared worn and showed evidence of carbon fouling.

The number 3 cylinder was removed; the piston and connecting rod remained in the cylinder. The interior portion of the piston and the connecting rod arm were black in color and both were thermally deformed. Portions of the piston had separated from the piston, and the connecting rod arm had separated. The rod arm bushing remained attached to the crankshaft journal; however, it was thermally deformed. The engine case showed internal deformation along with a piece of the bottom portion of the case separated from mechanical damage.

The oil pump was disassembled, and investigators noted wear of the gears, and metal particles in the housing. The oil filter was cut open with metal particles found on the filter element. Investigators further noted that all of the other connecting rods and main bearings showed signs of lubrication.

A review of the engine logbooks revealed that the engine had been overhauled on December 27, 2002, and installed on January 6, 2003; since that time the engine had accrued 1,482.0 hours. Routine maintenance was performed and 50-hour servicing/oil changes were complied with; there were no oil system related discrepancies noted.