CHI95FA148

Witnesses observed the airplane flying low with a rough running engine and black smoke coming from the exhaust pipe. They said the airplane entered a steep left bank, descended toward the ground in a steep pitch down attitude, leveled off at tree top height and pitched down again. It collided with the ground and bounced into the air, colliding with the ground a second time. The center fuselage, engine compartment, and inboard sections of the wings were consumed by fire. The carburetor contained composite floats which were charred and bellowed outward. The carburetor manufacturer published a mandatory service bulletin requiring replacement of the composite floats with metal ones. No record of this being done was observed in the accident airplane's engine or airframe logbooks.

History of flight

On May 7, 1995, at 1650 central daylight time (cdt), a Cessna 177B, N11372, piloted by a private pilot, was destroyed during a collision with the ground and subsequent fire following an uncontrolled descent. The 14 CFR Part 91 flight was not operating on a flight plan. Visual meteorological conditions prevailed at the time of the accident. The pilot was fatally injured. The flight departed Nappanee, Indiana, at 1640 cdt.

Witnesses reported seeing the airplane flying with a rough running engine that had black smoke trailing from its exhaust pipe. These witnesses observed the airplane flying in an easterly direction at a low altitude. The airplane, according to the witnesses, made a steep banked left turn and descended toward the ground in a steep nose down attitude. The airplane had leveled off close to tree top height and then pitched down into the ground, according to the witnesses. They said the airplane bounced about 10 feet into the air and, after striking the ground a second time, skidded about 100 feet to a stop. The airplane caught fire after the second ground collision, according to witnesses.

Personnel information

The pilot of N11372 possessed a private pilot certificate that was issued on May 1, 1979. A review of his pilot logbook revealed he had completed a biennial flight review on May 7, 1995. According to these records he had a total time of 1,682.6 hours. The logbook showed N11372 was the only airplane he had flown since January 5, 1985. Since that date he had accumulated 463.4 hours in N11372. According to the pilot's logbook, he had flown 3.6 hours between November 14, 1994, and May 7, 1995. The pilot's FAA third class medical certificate was issued on May 24, 1993.

Wreckage and impact information

N11372's wreckage trail was on an approximate heading of 285 degrees magnetic. A ground scar about 45 feet long, about 12 inches wide, and about 12 inches deep was at the beginning of the wreckage trail. Pieces of the nose wheel pant, cowl, and wing strut fuselage boot were found within the scar and about eight feet from the beginning of the scar.

A second ground scar was found approximately 70 feet from the first ground scar's ending point. The second scar was about 10 foot long, two feet wide, and 8 inches deep at the midpoint position. An ADF antennae blade was found in the center of this scar. The airplane's main wreckage was found approximately 110 feet from the ending point of the second ground scar.

White paint transfer marks were found on compressed dirt along the first half of the wreckage trail. Blue and white paint transfer marks were found on compressed dirt along the second half of the wreckage trail. Sections of the windshield and cowl were found scattered along the wreckage trail. The airplane's left door was found about 150 feet from the wreckage trail's start and about 50 feet south of the trail. Part of the fuselage was attached to the door's hinged side. The bottom, front, end of the door was crumpled aft about six inches.

N11372's fuselage was destroyed by fire between the dorsal fin and engine. The airplane's right wing had been consumed by fire from the wing root to about the one-third the way out from the wing root. The majority of its leading edge had been consumed by fire. The left wing was also consumed by fire from the wing root out to about one-quarter span.

The engine compartment had been involved in the post-crash fire. The engine was found resting on cylinders' number one and three. Wiring, including the sparkplug wires, had been fire damaged or destroyed. The dual magneto was consumed by fire, only the heavy steel parts remained. The engine driven fuel pump had been consumed by fire. The carburetor had portions of its exterior melted. One propeller blade had been fire damaged, about 50 percent of it was missing. The stub end of this blade had what appeared to be a melted surface appearance. The second propeller blade was bent aft about 70 degrees at the one-third span from its hub.

The engine rotated freely and no mechanical anomalies were found that would prevent it from producing power. Examination of the engine revealed number two and four cylinder's internal side of the combustion chamber area to be black in color. Piston tops for these cylinders were also black in color. The sparkplug electrodes for these cylinders' were black in color. The combustion chamber's and pistons of cylinders' number one and three were about 30 percent covered with a black coloring. The associated sparkplugs were partially blackened. The black coloring could be removed with a finger swipe.

The carburetor's two composite floats were expanded outward and blackened. The float's exterior structure was black in color. It had a flaky appearance and would have collapsed if any pressure were applied to its surface. The carburetor's venturi was a one piece unit. No metal was found in the engine oil sample taken from its sump. The oil filter's element was consumed mostly by fire. The muffler's flame tubes were intact with no visible damage.

The cockpit area, including the radios and instruments had been destroyed by fire. Control continuity between the primary flight control surfaces and the cockpit control mechanisms was established.

Aircraft information

N11372's airframe logbook showed its annual inspection had been completed on November 1, 1994. Its total airframe time was 1,958.7 hours upon completion of the annual. This airframe time, and the pilot's flight time in the airplane since its annual showed the airplane had 1,965.2 hours on it at the time of the accident.

The airplane was equipped with a Marvel-Schebler MA-4-5 carburetor. This carburetor, according to a Precision Airmotive Corporation's "Mandatory Service Bulletin" number MSA-1, required the removal of the composite float assembly. The bulletin stated: "Replace the existing composite float with a metal float." No record of service bulletin compliance could be found in the airframe or engine logbook.

Medical and pathological information

The autopsy on the pilot was conducted at the Goshen General Hospital, Goshen, Indiana, on May 8, 1995, by Dr. M. N. Garcia. The cause of death was shown as: "Light aircraft accident. Asphyxiation, aspirated blood, charred body." The FAA Toxicology and Accident research Laboratory located in Oklahoma City, Oklahoma, conducted the toxicological examination. No drugs, ethanol, cyanide, or carboxyhemoglobin were found.

Fire

Examination of the remaining airframe revealed no airstream sooting marks. Soot marks were not observed on the door's exterior or on the interior or exterior sides of its window.

The wreckage trail did not show evidence of preimpact fire. A fire scar was found on the ground area immediately surrounding the airplane. A wedge shaped burnt area was found to the right front of the airplane. The fire, according to fire officials attending the scene, was maintained by the airplane's fuel and combustible materials making up the airplane.

Additional information

The wreckage was released to Mr. A.G. Plumley of A.G. Plumley Incorporated, Merrillville, Indiana, on May 8, 1995. Mr. Plumley was representing the AIG Insurance Company, Chicago, Illinois.