NTSB Factual Report

HISTORY OF FLIGHT

On August 29, 2000, at 1722 hours Pacific daylight time, a Cessna 150L, N11919, was destroyed when it collided with terrain while maneuvering near Laton, California. The private pilot/owner was operating the airplane under the provisions of 14 CFR Part 91. The pilot and one passenger sustained fatal injuries. The local area personal flight departed a private strip on the pilot's farm at an unknown time. Visual meteorological conditions prevailed and no flight plan had been filed. The accident site's GPS coordinates were 36 degrees 24.862 minutes north latitude and 119 degrees 45.295 minutes west longitude.

Witnesses reported the pilot frequently flew over their home at low altitude. They observed him on those occasions to complete 360-degree turns as he opened his side window and conversed with them. On this occasion, the pilot flew by the north side of the home in a left turn at an estimated 300 feet agl. He opened his window and said, "hello." One of the ground witnesses invited him to come visit after his flight and he responded, "we will." The airplane continued the left turn, momentarily leveled out, then banked left and began to turn left again. By this point the airplane had completed 270 degrees of turn and was now east of the home. This turn initially appeared to be like others the witnesses previously observed. However, this time the bank angle continued to rapidly increase so that they observed the top of the airplane's wings. They observed a simultaneously rapid movement of the nose to a nearly vertical nose down position as the bank angle increased. The airplane came to rest in a walnut grove less than 0.1-mile from the witnesses' home.

The witnesses heard engine sounds the entire time they observed the airplane. They did not hear any sputtering, backfiring, or decrease in tone, and did not observe any smoke or flames. One witness thought the engine was speeding up as the airplane started down.

PERSONNEL INFORMATION

A review of Federal Aviation Administration (FAA) airman records revealed the pilot held a private pilot certificate with an airplane single engine land rating. An examination of the pilot's logbook indicated an estimated total flight time of 922 hours at the last entry dated September 22, 1996. The Safety Board investigator obtained a certified copy of the pilot's medical records. A third-class medical, with no limitations or waivers, was issued on July 16, 1999. On the application for this medical certificate, the pilot listed a total time of 1,150 hours. Based on maintenance logbook entries, the investigator estimated the pilot accumulated about 50 hours between this physical and the accident flight, with an estimated 22 hours in the last 90 days.

AIRPLANE INFORMATION

The airplane was a Cessna 150L, serial number 15075711. A review of the airplane's logbooks revealed an entry for an annual inspection on March 20, 2000, at a total time of 3,657.7 hours. A Teledyne Continental Motors O-200-A, serial number 250041, was installed on the airplane. Total time on the engine at the annual inspection was 3,240.7 hours; the entry listed time since overhaul as 1,733 hours. This entry recorded a tachometer reading of 75.6. The last maintenance logbook entry on May 19, 2000, indicated the mechanic replaced the ammeter at a tachometer time of 82.7. The reading at the accident scene was 107.4.

METEOROLOGICAL CONDITIONS

A routine aviation weather report (METAR) for Hanford was issued at 1653. It stated: skies clear; visibility 10 miles; winds from 300 degrees at 6 knots; temperature 82 degrees Fahrenheit; dew point 55 degrees Fahrenheit; and altimeter 29.85 inHg.

WRECKAGE AND IMPACT STATEMENT

The airplane came to rest on its right side under a walnut tree. The leading edges of both wings were crushed aft to the spar. Tree limbs were underneath the airplane and on top of the wreckage. The cabin area came to rest with the nose on a magnetic bearing of 130 degrees and with the empennage twisted counterclockwise about 45 degrees. First responders noted that both fuel tanks ruptured and blue colored fuel was leaking from the wings. All control cables were connected to their respective control surfaces and control continuity was established to the deformed cabin area. The nose gear separated and was found 18 feet from the cabin at its 7 o'clock position. A 2-foot-long section of the left aileron was 21 feet from the cabin at its 10 o'clock position. The right main gear separated and was 25 feet from the cabin at its 1 o'clock position. The propeller fractured and separated at the juncture of the propeller flange and crankshaft. The fracture surface was along an angular plane and exhibited an irregular surface. One propeller blade was bent aft at the tip and twisted toward the cambered side. The other blade exhibited an S-bend, with leading edge polishing and chordwise striations.

MEDICAL AND PATHOLOGICAL INFORMATION

The Fresno County Coroner completed an autopsy. The FAA Toxicology and Accident Research Laboratory, Oklahoma City, Oklahoma, performed toxicological testing of specimens of the pilot. The results of analysis of the specimens were negative for carbon monoxide, cyanide, and volatiles. A positive reading of 12.24 (ug/ml, ug/g) for salicylate, listed in Dorlan's Illustrated Medical Dictionary as a component of aspirin, was detected in the urine.

TESTS AND RESEARCH

Investigators from the Safety Board, Cessna Aircraft Company, and Teledyne Continental Motors examined the wreckage at Aircraft Recovery Service, Compton, California, on September 28, 2000. They removed the engine from the airframe, slung it from a hoist, and manually rotated it with the propeller. All valves moved in sequence, and they obtained thumb compression on all cylinders. They removed and examined the top spark plugs. Number three was oily; the rest were gray, which corresponded to normal operation according to the Champion Aviation Check-A-Plug AV-27 Chart. None of the spark plugs exhibited mechanical damage. Investigators obtained spark from the number one and two plugs during rotation; the harness was damaged on cylinder's three and four. The carburetor fuel bowl and finger screen were clean, and the floats were undamaged. The throttle valve moved freely through its entire range. The fuel selector valve was in the horizontal (on) position.

ADDITIONAL INFORMATION

The Safety Board released the wreckage to the owner's insurance agent. Cessna Aircraft Company and Teledyne Continental Motors were parties to the investigation.

NTSB Probable Cause

failure of the pilot to maintain an adequate airspeed while maneuvering, resulting in a stall at an altitude too low to allow recovery.