IAD03LA041

Shortly after takeoff, about 400 feet above the ground, the airplane made a 180-degree right turn, then a descending left turn, and impacted the ground in a steep, left-wing-low attitude. Subsequent examination revealed no evidence that the left wing's aft strut-to-spar attachment bolt was present at the time of impact, nor could the bolt be located in the wreckage or at the accident site. The accident flight was the first flight after the pilot/mechanic had completely rebuilt the airplane.

On March 27, 2003 at 1610 eastern standard time, an Aeronca CH-7A, N83519, was substantially damaged when it impacted terrain shortly after taking off from Mexico Farms Airport (1W3), Cumberland, Maryland. The certificated private pilot/mechanic was seriously injured, and the passenger received minor injuries. Visual meteorological conditions (VMC) prevailed, and no flight plan was filed for the local test flight conducted under 14 CFR Part 91.

According to the airplane's owner, he had hired the pilot/mechanic to restore it following 5 to 7 years of storage. This was the airplane's first flight since being completely disassembled and rebuilt.

Telephone interviews with both the pilot and the passenger revealed that neither had any memory of the accident flight; however, the pilot did state that in the weeks prior to the accident, he had fueled the airplane with aviation fuel and had performed several ground runs.

According to witness statements, the airplane took off from runway 09, then made a 180-degree climbing right turn to the west, attaining an altitude of approximately 400 feet above ground level. Shortly after passing abeam the threshold of runway 09, the airplane made a descending left turn, clipping several trees and a second-floor porch railing before impacting the ground and coming to rest on its left side, against the back of a residence.

A witness, who was working outside in her garden, described the engine sounds as being "loud and slow" prior to hearing the impact.

The airplane was examined on site by a Federal Aviation Administration (FAA) inspector. All of the wreckage was contained within the backyard of a single residence, with some evidence of impact with trees and another house immediately south of the accident site. Damage to both residences was superficial. The damage path indicated a steep, left-wing-low decent. The left side of the airplane was extensively damaged.

The wreckage was moved to a hangar and further examined. According to the inspector, rotational damage was observed on the propeller.

The propeller hub was rotated by hand, and thumb compression was obtained on all cylinders. Valve train continuity was established to the rear accessory drive. Examination of the top row of spark plugs revealed their electrodes were intact and light gray in color. The right magneto was damaged by impact; the left magneto was rotated by hand and delivered spark on all towers.

Examination of the fuel tank revealed 1 to 2 gallons of auto fuel. The fuel bowl-to-carburetor supply line was disconnected at the carburetor. Fuel flowed freely from the bowl. The carburetor inlet screen was not contaminated and the bowl was full of fuel. Throttle linkage continuity was established, although the throttle could not be operated due to impact damage. The throttle was found in the 'idle' position. The engine was not equipped with a mixture control.

Control cable continuity was established from the flight control surfaces to the cockpit. The cables exhibited tool-cut damage and "broomstraw" breakage. None of the terminus-point cable connections showed signs of pre-impact failure.

The Aeronca CH-7A was a high-wing airplane with a wooden wing spar supported by 'V' shaped struts. The bottom of each strut was attached at a single point to the fuselage, while the top of each strut was bolted to the underside of the wing spar at two attachment points, fore and aft.

According to the inspector, the aft strut attachment point was not connected to the left wing spar at the accident site. The aft strut/wing attachment hardware was not found in the wreckage of the airplane or at the accident site. The bolt holes in the wing spar and on the aft strut revealed no signs of damage or stress from impact. The bolt holes in the wing spar and on the forward strut revealed signs of stress and bolt-hole-elongation.

Following the accident, the pilot/mechanic told the investigator that he remembered installing all four strut/wing attachment bolts prior to the accident flight.

Weather conditions at Greater Cumberland Regional Airport (CBE), Cumberland, Maryland, 1 mile north of Mexico Farms, were reported at 1642 as winds at 150 degrees true at 14 knots, gusting to 18 knots, and clear skies with 10 miles visibility.

Mexico Farms Airport was an uncontrolled airport with a single 2,100-foot-long by 195-foot-wide turf runway, and a field elevation of 607 feet.