NTSB Factual Report

HISTORY OF FLIGHT

On May 30, 2003, about 0958 Pacific daylight time, a Cessna 172, N7301A, sustained substantial damage when it collided with mountainous terrain near the summit of Sherman Pass, approximately 11 miles east of Republic, Washington. The airplane was owned by the pilot, and was being operated as a visual flight rules (VFR) reconnaissance flight under the provisions of Title 14, CFR Part 91, when the accident occurred. The private pilot and observer aboard the airplane were fatally injured. Visual meteorological conditions prevailed for the flight that originated from the Ferry County Airport (R49) approximately 30 minutes prior to the accident. There was no post crash fire and no report of ELT activation.

A witness, who was traveling eastbound on State Route 20, reported that he observed the airplane traveling on a westerly heading (in the direction of the summit) just above the treetops on the north side of the highway. The witness stated the airplane was in a level flight attitude when it suddenly banked sharply to the left and entered a steep descent. He reported that he observed the airplane "…twist and dive" just before impacting terrain in a nose-low attitude.

The aircraft was being operated in support of a search for a missing person conducted by the Ferry County Sheriff's Office. The individual was reported missing on the evening of May 29. The following day, about 1800 hours (approximately 8 hours after the accident), the individual was located roughly two miles east of the accident site, along State Route 20.

The passenger of the airplane was the Under Sheriff of Ferry County. The pilot was a volunteer for the Sheriff's Office, as well as a volunteer pilot for Washington State Air Search and Rescue.

PERSONNEL INFORMATION

At the time of the accident, the pilot held a private pilot certificate with an airplane single-engine land rating. The pilot's flight time logbook indicated that he had accumulated approximately 953 total flight hours. The last logbook entry was dated November 8, 2002. All flight time was logged under the heading "Single-Engine Land." The logbook also indicated that the pilot had successfully completed a flight review on September 5, 2001.

Medical records obtained from the Federal Aviation Administration, indicated that the pilot held a third-class medical certificate dated September 27, 2001. The medical certificate carried limitations requiring the pilot to wear corrective lenses.

AIRCRAFT INFORMATION

The airplane, a 1956 Cessna 172 (serial number 29401), was powered by a Continental O-300 series engine rated at 145 horsepower. Maintenance records indicated that the airplane's last inspection, an annual inspection, was completed on July 17, 2002. The airplane had accumulated approximately 54 hours from the time of the inspection to the time of the accident.

METEOROLOGICAL INFORMATION

The closest official weather observation facility is located at Colville, Washington (KCQV), approximately 24 miles east of the accident location. The 1050 observation at KCQV reported, in part: visibility 20 statute miles; broken clouds at 15,000 feet; temperature 70 degrees F; dew point 45 degrees F.

WRECKAGE AND IMPACT INFORMATION

Personnel from the National Transportation Safety Board, Federal Aviation Administration and Cessna Aircraft accessed the wreckage site on May 30-31.

The wreckage was located on forested land at 48 degrees 36.84 minutes' north latitude and 118 degrees 27.91 minutes' west longitude. The elevation of the wreckage site was approximately 4,970 feet above sea level. The wreckage came to rest approximately 50 feet south (down hill) from a series of high-tension power lines. The span of the power lines generally track from east to west respectively, and are approximately 50-60 feet in height. No damage was noted to the power lines or associated support structures.

The first identified point of contact was a large conifer tree located approximately eight feet northwest of the wreckage. The tree had notable scarring and was sheared off approximately 10 feet from its base. A second tree, that had been uprooted, was found adjacent to the left wing assembly.

The airplane impacted terrain in a nose-low attitude, oriented on a magnetic heading of approximately 105 degrees. The forward section of the airplane, from the firewall forward, was buried in the impact crater. The fuselage, from the firewall aft, extended vertically from the crater.

The cockpit controls and instrument panel sustained extensive impact damage and a majority of the instrumentation was destroyed. The throttle control was observed in the forward position, approximately one inch from its stop. The mixture control was in the full rich position and the carburetor heat control was in the cold (forward) position. The magneto switch was observed in the "both" position and the key was broken off inside the switch assembly. The fuel selector was noted to be in the "both on" detent. Control cable continuity for the throttle, mixture and carburetor heat was established from cockpit to the engine assembly.

The right wing remained attached to the fuselage. Leading edge damage was noted along the entire span of the wing. The wing section was rotated in a forward direction and a large section of the inboard leading edge was crushed aft to the wing spar. The lift strut was detached from the wing assembly and located in the immediate area of the wreckage. U-shaped bending and leading edge damage was noted to the strut. The aileron and wing flap were found attached to their respective mounting points. Control cable continuity was established from the aileron to the control yoke. Control continuity was established from the flap assembly to the flap handle. An undetermined amount of fuel, straw in color, was observed in the right fuel tank.

The left wing remained attached to the fuselage. Large u-shaped crushing, consistent with a tree strike, was noted to the left wing. The crushing pattern extended from the leading edge to the trailing edge of the wing. The aileron and wing flap were found attached to their respective mounting points. Control cable continuity was established from the aileron to the control yoke. Control continuity was established from the flap surface to the flap handle. An undetermined amount of fuel, straw in color, was observed in the left fuel tank.

A series of parallel scratch marks were observed on both wings. The marks were noted on the bottom of the left wing, approximately three inches inboard of the last rib. The marks originated near the leading edge and ran aft approximately six inches. Similar type marks were observed on the trailing edge of the left wing, and on the fiberglass wing tip of the right wing.

Minimal damage was noted to the empennage and associated control surfaces. All fixed and movable control surfaces remained attached in their respective positions and control cable continuity was established from the control surfaces to the cockpit. The elevator trim tab was observed in the neutral position.

The propeller assembly was found as a unit attached to the crankshaft flange. Rearward crushing was noted to the propeller spinner. Spanwise aft bending, outboard leading edge damage and chordwise scratching was noted to propeller blade "A". S-type bending, chordwise scratching and leading edge damage was noted to propeller blade "B".

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy on the pilot was conducted by the Spokane County Medical Examiner's Office, Spokane, Washington, on June 02, 2003. According to the postmortem report, the pilot's death was attributed to "lacerations of the brain and brain stem."

The FAA Civil Aeromedical Institute (CAMI), Oklahoma City, Oklahoma, conducted toxicology testing on the pilot. According to the postmortem toxicology report, Trimethoprim was detected in the pilot's blood, liver and urine. The report also indicated that results were negative for carbon monoxide, cyanide, and ethanol, and illegal drugs (see attached toxicology report for specific values and test parameters).

TESTS AND RESEARCH

Representatives from the Spokane, Washington, Flight Standards District Office (FSDO) and Teledyne Continental Motors, examined the aircraft's engine at a storage facility in Deer Park, Washington, on June 18, 2003, and reported the following:

Extensive impact damage was noted to the engine and associated engine components. Sections of the exhaust and intake tubing were crushed and distorted. Both crankcase halves and cylinder assemblies were intact and showed no evidence of a mechanical failure. Valve train and accessory gear continuity was established by manually rotating the engine's crankshaft. Normal valve actuation was noted. Compression was produced in all six cylinders when the crankshaft was manually rotated. Internal examination of the piston cylinders revealed no evidence of mechanical malfunction. Both magnetos were damaged. They were both removed and produced spark when manually rotated. The bottom spark plugs were removed and normal operating wear patterns were noted.

The carburetor, which was found broken away from its mounting flange, was disabled during the on-site portion of the investigation. Trace amounts of fuel were observed in the carburetor bowl. The carburetor bowl was free of contaminants and the metal float was intact.

Examination of the airplane's engine revealed no evidence of a mechanical malfunction or failure.

ADDITIONAL DATA

On November 13, 2003, the airframe, engine and associated components were released to a representative of Phoenix Aviation Managers, Boise, Idaho.

NTSB Probable Cause

The pilot's failure to maintain airspeed resulting in a stall and subsequent loss of control during low altitude maneuvering.