History of Flight
On December 22, 2022, about 1518 Pacific standard time, a Cessna 150, registration N7032X, sustained substantial damage in an accident near Santa Monica Municipal Airport (SMO), Santa Monica, California. The pilot sustained minor injuries, and the passenger was fatally injured. The flight was conducted as a Title 14 Code of Federal Regulations Part 91 personal flight.
The pilot reported that the intended route was local, following the Pacific Ocean coastline northwest. After topping off the fuel tanks, the airplane felt “sluggish” during taxi to runway 21. The pilot canceled the takeoff, returned to the hangar, and shut down the engine. He checked tire pressure, then restarted and performed a magneto and carburetor heat check, which were normal. He then taxied and departed from runway 21.
During initial climb, about 575 ft agl, the pilot turned right to follow the coast near Ocean View Park. ADS-B data indicated that four minutes into the flight, over Sunset Beach, the airplane was at 1,025 ft agl and 70 mph. The pilot reported that carburetor heat was off, mixture rich, throttle full, and ignition in Both. He then heard a “bang” and made a left 180° turn. He contacted the SMO tower controller and attempted to return, but the descent rate increased, leading to a forced landing on the shoreline about 2,200 ft south of the Santa Monica Pier. The airplane touched down heading south in shallow water and nosed over.
Aircraft Information
Examination of maintenance logbooks revealed that the annual inspection was completed four months before the accident. At that time, engine time since overhaul was 1,737.0 hours, and total time was 3,344.0 hours. The engine had been overhauled on August 28, 1970, with a top overhaul in 1972. No additional logbook entries were made after the annual inspection. The engine manufacturer’s recommended time between overhaul is 1,800 hours or 12 years.
Wreckage and Impact Information
The accident site indicated that the airplane touched down heading southeast with the main landing gear contacting water, then nosed over. The airplane came to rest nose northwest, right wing west toward the ocean, left wing east toward the shore. The upper fuselage and both wings were submerged; first responders pulled the airplane to shore. The engine mounts sustained substantial damage.
Examination of the recovered wreckage showed no holes in the engine crankcase, and all accessories remained attached. The propeller could not be turned by hand, exhibiting binding and restriction. The spinner was crushed, attached by two of six hub bolts. About 5 quarts of oil were extracted from the sump.
The No. 1 piston was seized to the cylinder, with damage to the skirt. The No.1 piston rod and bearing were separated from the crankshaft; the connecting rod bolts were stretched and the bolt heads separated. The oil sump contained residual oil and metallic fragments.
Crankcase halves were disassembled; the crankshaft main bearings were intact with normal wear. Internal mechanical damage was observed at the No. 1 and 2 cylinder bays. The No. 2 connecting rod bearings showed thermal discoloration and metal deformation consistent with oil starvation. The No. 3 cylinder connecting rod bearings displayed similar thermal discoloration and deformation, with one bearing seized to the rod. The No. 4 cylinder connecting rod bearings showed only thermal discoloration.
The oil filter was unremarkable, and the oil pump showed no anomalies. The oil filter adapter and its components were undamaged. The oil sump pickup tube appeared unimpeded.