NTSB Factual Report

HISTORY OF FLIGHT

On November 20, 1996, about 2034 hours Pacific standard time, a Piper PA-28-236, N8447B, en route to Bermuda Dunes, California, experienced an in-flight breakup and crashed near Lost Hills, California. The aircraft was destroyed and the pilot received fatal injuries. The aircraft was operated as a personal flight by the pilot/owner when the accident occurred. The flight originated in Hayward, California, at 1910. Instrument meteorological conditions prevailed from about 4,000 to 14,000 feet msl near the accident site, and no flight plan was filed.

The aircraft was reported overdue about 0220 on November 21, 1996, by family members concerned that the aircraft had not reached its destination. An ALNOT was issued and a search was initiated. The main aircraft wreckage was located in an agricultural field near the intersection of County Line and Corcoran roads about 0800 by Kern County Sheriff's deputies. The wings and tail section were found north of County Line road in Tulare county.

A review of Federal Aviation Administration (FAA) Air Traffic Control records disclosed no evidence that any preflight or in-flight weather briefings, communications, or other in-flight services had been provided, nor had the aircraft been positively identified on radar by any facility.

PILOT INFORMATION

The pilot obtained his private pilot certificate on December 23, 1991. The pilot's logbook showed that his last simulated instrument flight was 0.9 hours on June 8, 1992. The pilot's last flight was of 4.2 hours duration on August 3, 1996, in the accident aircraft. The logbook also showed that the pilot had flown from Hayward to Bermuda Dunes on several prior occasions.

AIRCRAFT INFORMATION

The aircraft, engine, and propeller logbooks were not located. Records found onboard the aircraft indicated that a propeller strike inspection had been performed in accordance with Lycoming Service Bulletin 201D. However, in the record, there was no report that AD 91-14-22, required to prevent loosening or failure of the crankshaft gear retaining bolt after a propeller strike, had been completed.

METEOROLOGICAL CONDITIONS

A Safety Board meteorologist prepared a meteorological report for the time and location of the accident. According to recorded weather data, there were clouds and light rain near the accident site at the time of the crash. The Meteorology Group Chairman's Factual Report is appended to this report.

WRECKAGE AND IMPACT INFORMATION

The position of the fuselage was 35 degrees 47.3 minutes east latitude and 119 degrees 35.0 minutes west longitude, headed 148 degrees. The elevation of the accident site was about 150 feet msl.

The outboard sections of both main wings, along with the vertical stabilizer and the outboard sections of the stabilator, were found approximately 0.25 miles northeast of the fuselage. The position of the left horizontal stabilizer was 35 degrees 47.4 minutes east latitude by 119 degrees 34.6 minutes west longitude. The position of the right horizontal stabilizer was 35 degrees 47.5 minutes east latitude by 119 degrees 34.7 minutes west longitude. The right outboard wing section was located 35 degrees 47.4 minutes east latitude by 119 degrees 34.7 minutes west longitude. The left outboard wing section was located 35 degrees 47.6 minutes east latitude by 119 degrees 34.6 minutes west longitude. The vertical stabilizer was located 35 degrees 47.5 minutes east latitude by 119 degrees 34.6 minutes west longitude.

The fuselage impacted a rain softened open field in an inverted attitude. There was no evidence of any lateral or longitudinal movement after the initial impact.

The fuselage exhibited compression deformation and a partial separation aft of the rear seats. The left wing separated about 7.5 feet outboard of the wing root. The left flap remained attached to the inboard wing section. The left fuel tank was ruptured.

The left aileron was separated about midspan, but the outboard section remained attached to the main wing. The aileron counterweight was separated from the aileron and was not located during the wreckage examination.

The top spar cap of the left wing was bent downward at its fracture point and exhibited an S-bend. The bottom spar cap was bent upward at its fracture point. The web between the spar caps exhibited crushing and tearing.

The right wing separated about 8 feet outboard of the wing root. The right flap remained attached to the inboard section of the wing. The right fuel tank was ruptured.

The right aileron remained attached to the outboard section of the wing. The aileron counterweight was separated from the aileron and was not located during the wreckage examination.

The top spar cap was bent upward at its fracture point. The bottom spar cap was separated, but did not exhibit bending. The web between the spar caps was bowed and torn.

The vertical stabilizer separated at its front and rear attachment points. The skin was crushed on the left side and torn on the right side. The counterweight and fairing had separated and were found along the debris path. The rudder remained attached to the stabilizer at its lower fitting. The rudder cables were attached to the horn and the rudder stops did not display any damage.

The right and left horizontal stabilizers were separated outboard of their attachment fittings. The center section of the stabilizer remained attached to the airframe. The outboard ends of the center section exhibited upward bending on the left side and downward bending on the right. The control stops did not display any damage and the trim drum assembly remained attached.

The left horizontal stabilizer was separated outboard of its attachment fitting. The skin surface exhibited span wise crushing and an upward bend. The right side also separated outboard of its attachment fitting. The section exhibited span wise bowing in an upward direction. The skin surface at the point of separation on both sections exhibited tearing.

The engine crankshaft was rotated by hand in both directions and drive train continuity and valve action were confirmed. A thumb check confirmed compression and the proper firing order for cylinders No. 2, 3, 4, 5, and 6. However, it was found that the No. 1 cylinder was producing less compression than the remaining cylinders. After the cylinder was removed from the engine and examined, dirt was found under the valve seat. The push rods displayed impact damage.

The oil suction screen was examined and was found to be free of contamination.

The single drive, dual magneto had separated from the engine. Under hand rotation, the magneto produced a spark at all 12 plug leads. The magneto drive was intact and the safety wire was in place.

The spark plugs were found to be secured in all positions with the leads attached. The top plugs were removed and examined. Except for the No. 3T plug, all the plug electrodes were undamaged and displayed colors consistent with normal operation according to the Champion "Aviation Check-a-Plug" chart. The No. 3T plug showed some rust buildup.

The carburetor had separated from the engine and the throttle and mixture controls had separated from the carburetor. The fuel pump had also separated from the engine.

The vacuum pump was found in its mount. Its drive was intact and undamaged and rotated freely when turned by hand. The pump was disassembled and was found to be undamaged internally.

The propeller assembly had separated from the engine at the crankshaft flange and exhibited evidence of impact damage.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy was conducted on November 22, 1996, by the Kern Coroner's Division, with specimens retained for toxicological examination. The toxicological test results were negative for alcohol and all screened drug substances, except for acetaminophen and Salicylate.

The coroner reported the presence of atherosclerosis with 80 percent occlusion of the left anterior descending artery and 75 percent occlusion of the right coronary artery.

The pilot's medical certificate required him to wear glasses for distance vision.

ADDITIONAL INFORMATION

The aircraft was retrieved by Aircraft Recovery Services and taken to their storage facility in Compton, California. The aircraft was released to a representative of the registered owner on February 19, 1997.

NTSB Probable Cause

The pilot's continued VFR flight into instrument meteorological conditions, which led to spatial disorientation and loss of aircraft control, and the pilot exceeding the aircraft's design stress limits during an attempted recovery. The noninstrument-rated pilot's failure to obtain a weather briefing, the weather conditions, and the dark night were factors.