Accident Overview
On July 18, 2013, at approximately 1011 eastern daylight time, a Beech 23, registration N2333Z, was substantially damaged after experiencing a loss of engine power and subsequently striking a tree and houses. The accident occurred shortly after takeoff from Suburban Airport (W18) in Laurel, Maryland. The private pilot, who was the sole occupant, was seriously injured. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight, which was destined for Gettysburg Regional Airport (W05) in Gettysburg, Pennsylvania.
Pilot Account
The pilot reported waking at 0830 and leaving for the airport, arriving at approximately 0910. He performed a preflight inspection and visually confirmed the fuel tanks were full, as he had topped them off two days earlier. He selected the left fuel tank before taxiing and conducted an engine run-up lasting about 15 minutes, including magneto and carburetor heat checks, both of which he described as normal. Prior to departure, he selected one notch of flaps and proceeded with takeoff from runway 03.
The pilot stated that everything was normal until the aircraft reached approximately 250 feet over the departure end of the runway, at which point the engine suddenly lost power. He switched fuel tanks and activated the boost pump in an attempt to restore engine power, but the engine did not respond. He maneuvered the aircraft left and then right, and his last recollection was seeing a gray house.
Witness and Radar Data
Air traffic control data indicated the pilot had filed a VFR special flight rules area (SFRA) flight plan and obtained a beacon code for the Washington SFRA, but he was unable to contact ATC before the power loss. Radar data showed the aircraft reached a peak altitude of 300 feet after takeoff, but about nine seconds later, at 10:10:20, it descended below radar coverage.
A witness reported observing the aircraft flying west to east when the left wing "dropped" and the plane headed toward the ground. She then heard a "boom" and saw smoke.
Aircraft and Engine Examination
Post-accident examination revealed that the aircraft initially struck a 40-foot-tall pine tree about 24 feet above its base, fracturing the tree into two sections. It then struck the northwest corner of a house, separating the right wing from its mounting. The aircraft continued approximately 70 feet, struck the west side of another house, fracturing the fuselage aft of the baggage door, and came to rest against the southwest side of that residence, with the left wing penetrating the front of the house.
Examination of the wreckage did not reveal any preimpact structural or control failures. Control continuity was established from the flight controls to the rudder pedals and control wheel. Both wing fuel tank caps were closed and locked; approximately 12 ounces of fuel was recovered from the left tank, consistent with 100LL aviation gasoline, with no water detected. The fuel selector was found in the right wing tank position, the throttle full open, mixture full rich, carburetor heat off, and fuel boost pump off.
The propeller remained attached to the crankshaft flange, with one blade curved aft about 10 degrees and the other bent aft about 45 degrees, both exhibiting chord-wise abrasions and paint transfer. The engine was still attached to the firewall. Examination of the engine compartment revealed bird nests, bird excrement, and a red cloth protruding from the engine combustion air inlet opening, blocking it. The cloth was identified as the jacketing from a foam-filled cowl plug. The engine rotated freely, with continuity confirmed and suction and combustion observed in all cylinders.
The carburetor was partially disassembled and contained liquid with the odor of aviation gasoline; no water was detected. A mud dauber wasp nest approximately the size of a golf ball was found in the carburetor throat (venturi) below the main fuel nozzle. The engine-driven fuel pump produced air at the outlet when actuated by hand. Both magnetos produced spark, and spark plugs appeared normal.
Maintenance and Background
The aircraft was manufactured in 1962 and equipped with a 160-horsepower engine overhauled in 1992. Its most recent annual inspection was completed in January 1998 at 4,719 total hours; at the time of the accident, the aircraft had 4,997.56 total hours. The pilot reported 3,571 total flight hours.
Documents found in the wreckage indicated that some components, including magnetos, attitude indicator, directional gyro, fuel filler caps, wingtips, and transponder, had been replaced or worked on without entry into the aircraft or engine logbooks. The pilot intended to deliver the aircraft to a potential buyer who had paid for it about one year prior but had not completed the sale. A mechanic who inspected the aircraft about two months before the accident described it as in "deplorable condition" with numerous issues, including non-airworthy status. The pilot later stated that the aircraft had sat unattended for seven months without cowl plugs after the buyer removed the remaining one, and he cleaned bird nests and debris from the engine compartment two days before the flight.
Conclusion
The investigation did not identify any preimpact malfunctions of the aircraft or engine. The evidence indicated that the engine power loss likely resulted from the blockage of the combustion air intake by the cowl plug cloth and the presence of a mud dauber nest in the carburetor, which disrupted the fuel-air mixture. The pilot's actions during the emergency were consistent with attempting to restore power and maneuvering to avoid obstacles.