History of the Flight

On December 31, 1993, about 1535 hours Pacific standard time, a Grumman AA-1C, N39036, crashed during takeoff from Santa Paula, California. The airplane was being operated as a visual flight rules (VFR) cross-country flight to Oxnard, California, when the accident occurred. The airplane, operated by Aero-Flite, Oxnard, California, was destroyed by impact and postimpact fire. The certificated private pilot received fatal injuries. A passenger received serious injuries. Visual meteorological conditions prevailed.

The passenger reported that after departure the airplane began to lose power. The engine was not running rough or missing; however, it sounded as if it was not developing full power. The airplane only climbed to about 70 feet above the ground (agl). The passenger heard the stall warning horn sound several times while the pilot was performing several emergency procedures. The pilot began a left turn to return to the airport. During the turn, the passenger heard the stall warning horn again and the airplane rapidly descended into a river bottom area. The airplane came to rest inverted in about 3 feet of water. The passenger indicated that he was under water about 1 minute until he released his seat belt and exited the airplane onto a nearby sand bar.

A small fire erupted from the right wing root area that was extinguished by rescue personnel. The pilot remained trapped in the wreckage.

A witness reported that after departure the airplane wings appeared to be rocking. The airplane was not trailing any smoke. From about 50 feet above the ground, the airplane's left wing suddenly dropped and the aircraft descended almost straight down into the water.

The accident occurred during the hours of daylight at latitude 34 degrees, 20.22 minutes north and longitude 119 degrees, 04.23 minutes west.

Crew Information

The pilot held a private pilot certificate, issued on September 22, 1993, with airplane single-engine land rating. The most recent second-class medical certificate was issued to the pilot on October 12, 1993, and contained the limitation that correcting lenses be worn while exercising the privileges of his airman certificate.

According to the pilot's logbook and airplane rental records, his total aeronautical experience consisted of about 133 flight hours, of which 4.5 were accrued in the accident airplane. In the preceding 90 and 30 days prior to the accident, the logbook reflects a total of about 30 and 4.5 hours, respectively, flown.

Aircraft Information

The airplane had accumulated a total time in service of 2,311.53 flight hours. Examination of the maintenance records revealed that the most recent annual inspection, with an annual endorsement, was accomplished on October 16, 1992. A 100-hour inspection was conducted on October 18, 1993, 87.53 flight hours before the accident. A Federal Aviation Administration (FAA) airworthiness inspector, Van Nuys Flight Standards District Office, reported that although the 100-hour inspection did not have an annual inspection endorsement, it met the scope and detail of an annual inspection and was sufficient for FAA purposes.

The engine had accrued a total time in service of 188 hours of operation since new. The maintenance records note that the engine was installed in the airplane on October 16, 1992. The annual inspection endorsement and 100-hour inspection as noted above, were accomplished on the dates specified for the airframe. A 50-hour inspection, including an oil change, was conducted on December 8, 1993, 23 hours of operation before the accident.

Fueling records from the operator established that the aircraft was last fueled on December 31, 1993, with the addition of 10.0 gallons of 100ll octane aviation fuel, which filled both fuel tanks. Examination of the maintenance and flight department records revealed no unresolved maintenance discrepancies against the aircraft prior to departure.

Meteorological Information

The closest official weather observation station is Camarillo, California, which is located 7 nautical miles south of the accident site. At 1448 hours, a surface observation was reporting in part: Sky condition and ceiling, 20,000 feet, thin broken clouds; visibility, 50 miles; temperature, 65 degrees F; dew point, 40 degrees F; wind, 230 degrees at 6 knots; altimeter, 30.06 inHg.

Aerodrome and Ground Facilities

The Santa Paula Airport is equipped with a single, hard-surfaced runway on a 040 to 220 degree magnetic orientation. Runway 22 is 2,650 feet long by 40 feet wide. The Santa Clara River, with a wide area of dry river bottom, is oriented parallel and south of the runway.

Wreckage and Impact Information

National Transportation Safety Board investigators examined the airplane wreckage at the accident site on January 1, 1994. The wreckage examination revealed that the airplane struck soft, muddy ground in a near-vertical nose-down attitude in about 3 feet of water located along a river bottom area that parallels the runway.

All of the airplane's major components were found at the main wreckage area. The left wing exhibited spanwise leading edge aft crushing from about midspan outboard the tip. The crushing damage was more evident on the upper surface at the leading edge. The outboard tip was crushed in an aft and downward direction.

The right wing exhibited aft crushing and folding of the leading edge from about midspan to the tip. The inboard half of the wing exhibited upward crushing on the underside of the leading edge.

Due to the impact damage, Safety Board investigators were unable to operate the flight controls by their respective control mechanisms; they were, however, able to establish continuity of the flight controls to the cabin/cockpit area. The flight control surfaces remained connected to their respective attach points; however, the torque tube control to the flaps and ailerons were both broken at the wing root area.

The wings remained above the waterline and a postcrash fire at the right wing exhibited charring and destruction centered at the bottom, inboard portion of the right wing area and bottom floor area of the passenger seat. The instrument panel was extensively damaged by the impact. Safety Board investigators, however, obtained some instrument readings (see Supplement B for details).

The propeller and starter ring assembly separated from the engine crankshaft. One propeller blade was bent aft about 45 degrees, about 12 inches outboard from the hub. The blade did not exhibit any leading edge gouging, chordwise scratching, or torsional twist. The second blade exhibited aft bending about 6 inches inboard from the tip and had heavy leading edge gouging at that portion of the blade tip. The second blade also exhibited substantial torsional twist, slight "S" bending, and small leading edge scratches oriented on the chambered side of the blade at a 45-degree angle from the leading edge.

The engine sustained impact damage to the underside and front portion of the engine and was crushed aft and downward into the firewall. Initially, the crankshaft could not be rotated 360 degrees. The No. 1 cylinder had a large amount of mud and water in the cylinder. Flushing of the cylinder enabled Safety Board investigators to rotate the crankshaft 360 degrees.

Gear and valve train continuity was established. Thumb compression in the No. 2,3, and 4 cylinders was noted when the crankshaft was rotated by hand. A moderate amount of thumb compression was noted in the No. 1 cylinder. The oil suction and pressure screens were free of contaminants.

The right magneto remained attached to the engine and sustained impact damage and could not produce spark upon hand rotation. The left magneto separated from the engine and produced spark at all terminals upon hand rotation.

The dual electrode spark plugs exhibited no unusual combustion signatures. The No. 1 cylinder spark plugs were coated with oil, sand, and mud. The No. 2 plugs were wet with water and oil. The top No. 3 and 4 plugs were dry. The bottom No. 3 plug was wet with water and oil, and the No. 4 bottom plug was dry.

The carburetor contained a mixture of fuel and water in the bowl. No damage was evident to the venturi or the metal float. The carburetor inlet fuel screen was free of contaminants. The wing fuel tank screens were free of contaminants.

The mechanical fuel pump remained attached to the engine; however, was fractured at the top of the housing. The diaphragm was intact and produced suction sounds when hand activated. The electric fuel pump contained a small amount of fuel. When electrical power was applied to the pump, it activated and produced pumping action.

Medical and Pathological Information

A postmortem examination of the pilot was conducted by the Ventura County Office of Medical Examiner, 3291 Loma Vista Rd., Ventura, California, on January 1, 1994. The examination revealed that the cause of death for the pilot was attributed to asphyxiation by drowning. No preexisting conditions were noted during the examination which would have adversely affected the decedents abilities to pilot an aircraft.

A toxicological examination of the pilot was conducted by the FAA Civil Aeromedical Institute (CAMI) on April 4, 1994, and was negative for all screened alcohol or drugs.

Additional Information

Wreckage Release

The Safety Board released the wreckage, located at Air Services Inc., Santa Paula, California, to the owner's representatives on February 15, 1994. No parts or components were retained by the Safety Board.

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