NTSB Factual Report

History of the Flight

On June 19, 1996, at 1343 hours Pacific daylight time, a Beech C23, N66343, collided with a light post during an emergency landing after takeoff from the Burbank Airport, Burbank, California. The collision occurred about 1 mile east of the airport in the city of Los Angeles. The airplane was destroyed and the certificated private pilot and his two passengers received fatal injuries. The airplane was being operated by Riverside Air Service, Riverside, California, as a rental airplane. The flight was destined for Palo Alto, California. Visual meteorological conditions prevailed at the time and a visual flight rules flight plan was filed.

The pilot had flown the airplane solo from the Riverside Municipal Airport to the Burbank Airport earlier in the day. After landing, the pilot taxied and parked the airplane at Mercury Air Center. There was no evidence found of any discrepancies with the airplane during the first flight. The pilot met with his parents and the three boarded the airplane. The pilot started the engine and taxied for departure.

According to witnesses, the airplane's engine stopped after takeoff from runway 8. The airplane was observed to enter a nose-down attitude and descended below buildings and trees on the horizon.

Pilot Information

The pilot held a private pilot certificate which was issued on September 5, 1982, with an single engine airplane rating. The most recent second-class medical certificate was issued to the pilot on November 30, 1995, and contained the limitation that correcting lenses must be worn while exercising the privileges of his airman certificate.

According to the pilot's logbook, his total aeronautical experience consists of about 147 hours, of which 4 were accrued in the Beech C23. The pilot's logbook lists a total of 10 hours flown in the preceding 90 days before the accident, none of which was in the Beech C23. The pilot accomplished a biennial flight review on January 9, 1996, logging 1 flight hour in the Beech C23.

Aircraft Information

The airplane and engine accumulated a total time in service of 3,338 hours. Examination of the maintenance records revealed that the most recent annual inspection was accomplished on September 28, 1995, 53 flight hours before the accident. In addition, a 50-hour inspection was completed on June 18, 1996, about 4 flight hours before the accident.

The engine was the same that was installed in the airframe at the time of airplane manufacturer. The maintenance records note that a major overhaul was accomplished on June 21, 1995, about 1,692 hours before the accident. Annual and 50-hour inspections were accomplished by company maintenance personnel on the dates specified above for the airframe.

Review of the airplane's maintenance records revealed that 15 discrepancies were noted during the recent 50-hour inspection. The first discrepancy was an inoperative electric fuel pump. The company mechanic indicated he cycled the pump circuit breaker and found the pump operational.

The fourth discrepancy noted the left magneto had over a 200 engine rpm drop during the magneto check. The mechanic indicated he re-timed the magnetos to the engine and the discrepancy was resolved after an operational check.

Meteorological Information

The closest official weather observation station was at the Burbank Airport. At 1347, a scheduled record surface observation was reporting in part: sky condition and ceiling, 20,000 feet scattered; visibility 7 statute miles; temperature 84 degrees Fahrenheit; dew point 60 degrees Fahrenheit; winds 170 degrees at 14 knots; altimeter 29.85 inHg.

Wreckage and Impact Information

The airplane came to rest at latitude 34 degrees 12.393 minutes north and longitude 118 degrees 20.598 minutes west. The accident site is located on the north side of Cohasset street about 50 feet east of the Interstate 5 overpass. The left wing struck the top of a 30-foot-high street light pole at the wing root, rupturing the left fuel tank. The base of the pole was located next to the curb on the concrete sidewalk. The airplane traveled north across the sidewalk, sliding down the pole, and struck the top of a 6-foot-high fence impaling the fuselage aft of the rear seat and the right wing at the fuel tank on the two vertical fence posts. The airplane came to rest about 6 feet beyond the fence in a 45-degree nose-down attitude with the empennage being supported by the fence post at a 30-degree angle.

The local fire department dispensed fire fighting foam on Cohassett street to prevent a fire erupting from fuel vapors. After the foam had dispersed, the street was covered with spots in the asphalt surface from the fuel. There was also a aroma of aviation gasoline present. Fuel was found under the right wing when the wreckage was lifted and was noted dripping from the area of the carburetor.

The cockpit and instruments were destroyed. The magneto switch was found in the both position. The throttle was found in a mid range position, and the mixture control was found in the full rich position The flap handle was in the up position. The fuel boost pump switch was destroyed. Control continuity was established for all flight and engine controls.

All three occupants were wearing seat belts. The pilot and front seat passenger were also wearing shoulder harnesses. The rear seat passenger was not wearing the available shoulder harness.

The propeller remained attached to the engine. One blade was found bent and twisted between the engine and the ground. A gouge was found in the leading edge about 8 inches from the tip. The other propeller blade was protruding out in front of the engine cowling and was bent aft.

Medical and Pathological Information

A post mortem examination was conducted on the pilot by Los Angeles County Coroner's Office with specimens retained for toxicological examination. The specimens were sent to the Federal Aviation Administration's Civil Aeromedical Institute (CAMI) for analysis. The results of the pilot's toxicological analysis revealed positive results for ethanol. According to the CAMI report, 10.00 mg/dl concentration was found in vitreous fluid. No ethanol was detected in blood or urine samples.

Tests and Research

Electric Fuel Boost Pump

The fuel boost pump was removed from the airframe and examined. There was no evidence found of any fuel leaking or damage to the electrical wiring harness at the pump. There was a dent found on the outside of the sealed end of the pump. The dent was in the area of an open internal cavity. There was no evidence found that the dent would interfere with the reciprocating action of the pump internal mechanism or the electrical coil. The pump would not operate when a 12-volt direct current was applied. The resistance through the coil was measured at 2.4 ohms with a multimeter and found to be below the 21.1 to 23.4 ohm specifications found in the manufacturer's drawings. There was no evidence of the mechanical failure or malfunction found with the pumps internal reciprocating mechanism. The pumps internal screen filter was found free of any contaminants that would obstruct the flow of fuel.

The fuel boost pump also had an inked stamped date of May 1979. The pilot operating handbook for the airplane indicates the fuel boost pump should be replaced at engine overhaul. The handbook also indicates an engine overhaul interval of 2,000 hours. There was no evidence found in the airplane maintenance records of the fuel boost pump being replaced since airframe manufacture.

Engine Examination

The engine was examined on July 2, 1996, At Lynn's Aircraft Engines, El Monte, California. The left magneto, the diaphragm fuel pump, and the vacuum pump, all mounted on the accessory gear box exhibited impact damage that precluded rotation of the engine. The engine was disassembled and there was no evidence found of mechanical failure or malfunction with the rotating or reciprocating engine parts.

Examination of the right magneto revealed evidence of electrical arcing in the distributor block, the electrode finger, and at the coil. The electrode finger was also found loose. The electrode finger would rotate about 15 degrees independent of the shaft on the nylon gear. There was no evidence of malfunction or failure found with the left magneto.

The diaphragm fuel pump was disassembled and examined. There was impact damage found in the valve cover assembly at the inlet port and the vent ring was fractured. There was no evidence found of damage to the diaphragm. The pump was then reassembled and the lever actuated. Vacuum pressure was noted at the fuel inlet and compression pressure was noted at the fuel outlet.

Pilot Operating Handbook

The pilot operating handbook for the airplane states: "The most probable cause of engine failure would be the loss of fuel flow or improper functioning of the ignition system." The emergency procedures section of the handbook specifies the fuel boost pump be on for engine failure after liftoff and in flight. The normal procedure section also indicates the magnetos be checked and the boost pump be on before takeoff.

Wreckage Release

The wreckage was released to the representatives of the owner on July 2, 1996. The Safety Board retained the airplane's electric boost pump and right magneto for further examination. Both were released to the owner's representative on August 7, 1996.

NTSB Probable Cause

company maintenance personnel's inadequate service of the magneto system, and their failure of to replace the electric fuel boost pump, which led to a malfunctioning right magneto and an inoperative fuel boost pump. The inoperative fuel boost pump made it impossible for the pilot to accomplish the published emergency procedure for the engine failure.