History of Flight
On October 13, 2012, at about 1215 Pacific daylight time, a Piper PA-38-112, registration N4309E, collided with terrain following a loss of engine power during landing at Corona Municipal Airport, Corona, California. The commercial pilot, who was also the owner, sustained minor injuries. The airplane was substantially damaged. The local flight had departed Corona about 1115. Visual meteorological conditions prevailed, and no flight plan was filed.
The pilot reported that during the landing approach he performed his pre-landing checks. Shortly after turning on the auxiliary fuel pump, the engine lost all power. He performed troubleshooting procedures, but engine power did not increase. The airplane was on the left downwind leg of runway 07. Concerned that he did not have enough altitude to turn toward the runway, the pilot elected to land directly ahead in a field. During the approach, the right wing struck a tree, and the airplane descended underneath a power line, striking the airport perimeter fence and coming to rest in a field. Substantial damage occurred to the right wing, firewall, and tailcone.
Aircraft Information
The low-wing, single-engine airplane was manufactured in 1978 and equipped with a Lycoming O-235-L2C engine, serial number L-16453-15. Maintenance records indicated that the engine was overhauled and installed in 2004. At the time of the most recent annual inspection, dated March 3, 2010, the engine had accrued 115 hours since overhaul, and the airframe had 2,021 flight hours. The engine tachometer indicated 2,075.06 hours at the accident site. The pilot reported that the airplane was stored at an outdoor tie-down spot at Corona Airport.
Examination Findings
Aircraft recovery personnel reported draining about 2 gallons of fuel from the left tank during recovery. The right tank was breached, and a 6-foot-long by 2-foot-wide fuel stain was present on the ground. During the subsequent airframe examination, an additional 2 gallons of fuel was observed in the left tank. The fuel lines from the tanks to the carburetor inlet were full and unobstructed. The gascolator bowl contained light-colored fluid consistent with aviation gasoline, and its filter screen was free of debris. The fuel selector valve was found in the right tank position; it could be moved by hand, but crumpled airframe structure impeded smooth operation of the handle. The electrically driven fuel pump issued fuel when engaged.
Examination of the wing tank vent ports, located underneath each wing, revealed that they were completely plugged by a mud-like substance. The ports were removed, and the obstruction appeared consistent with Mud Dauber (wasp) debris. The fuel tank filler caps were of the vented type; the vent flapper valve was intact and opened appropriately with low air vacuum.
Carburetor
The Precision Airmotive Carburetor, model MA-3A, remained undamaged and firmly attached to the intake manifold. The fuel mixture, throttle, and carburetor heat linkages were intact and continuous to their respective cabin controls, and moved smoothly. The airbox and filter assembly sustained crush damage. Although the forward surface of the filter element was coated in a wax-like substance, the filter passed air when blown. The fuel inlet screen was free of debris.
The carburetor bowl was about half full with clear, blue-colored fuel. The brass float appeared intact and free of leaks. The float valve was intact, pliable, and free of contamination. A wasp-like insect was at the bottom of the bowl, adjacent to the bowl drain plug and mixture metering sleeve. Further examination of the metering valve revealed the head of a wasp-like insect wedged within the valve's inner sleeve, positioned adjacent to the fuel channel hole in the carburetor body.
The design of the carburetor bowl allows two direct paths to atmospheric pressure: the drain plug with two 3/32-inch-wide drain channels, and the atmospheric bowl vent. The vent opening is 1/4-inch-wide at the carburetor air inlet, and the channel continues to a 3/16-inch orifice in the roof of the fuel bowl. Carburetor induction air enters a chin scoop intake in the lower airbox cowling, flowing through the filter and into the carburetor airbox. The airbox incorporates a positive shut-off heat intake; when carburetor heat was selected, unfiltered induction air was drawn through a hose attached to a muffler shroud.
Engine
The engine sustained minimal damage, and post-impact examination did not reveal any anomalies that would have precluded normal operation.