NTSB Factual Report

HISTORY OF FLIGHT

On June 11, 2006, at 1605 Pacific daylight time, a Cessna 152, N452WC, experienced a loss of engine power and nosed over during a forced landing in Camarillo, California. Western Cardinal, Inc., was operating the airplane under the provisions of 14 CFR Part 91. The certified flight instructor (CFI), who held a commercial pilot certificate, was not injured, and the student pilot sustained minor injuries. The airplane was substantially damaged. The local instructional flight departed from Camarillo Airport about 1515. Visual meteorological conditions prevailed and a flight plan had not been filed.

In both a written statement and conversation with a National Transportation Safety Board investigator, the CFI reported that the purpose of the flight was for student pilot to practice private pilot maneuvers. The airplane departed with full fuel in both wing tanks. After about 45 minutes in flight, he began a demonstration of a simulated emergency approach to landing. He configured the airplane for the maneuver and started the demonstration in a practice area north of the departure airport. The CFI stated that he was the sole manipulator of the flight controls, while the student read the engine troubleshooting checklist aloud.

At 3,500 feet mean sea level (msl) the CFI configured the airplane for the best glide speed and began a descent with the throttle in the "out" (idle) position. As part of the maneuver he pushed the throttle control knob forward every altitude loss of 500 feet in an attempt to temporarily increase revolutions per minute (rpm) and "clear" the throttle. While the airplane was about 1,500 feet msl and on the simulated base leg of the traffic pattern, the CFI pushed the throttle forward. The engine did not respond normally and sounded as though it was winding up. For several seconds the CFI could audibly distinguish a revolutions per minute (rpm) increase (about 100 rpm), as if only one piston were firing. The engine subsequently quit and the propeller stopped. He attempted to restart the engine by using the engine troubleshooting checklist, but it failed to respond.

The airplane touched down in a soft dirt field and nosed over, coming to rest inverted. The wreckage was located about 5 to 6 miles northwest of the Camarillo Airport. The airplane incurred damage to the firewall. The CFI added that the carburetor heat control was in the "on" position from the beginning of the maneuver until the accident, where it had been pushed in as a result of the impact.

Personnel that recovered the wreckage shortly after the accident stated that they found 15 to 20 gallons of fuel in the wing tanks. They indicated that they drained fuel from the fuel line that connects the carburetor to the gascolator. The carburetor heat control was found in the forward (off) position.

PERSONNEL INFORMATION

According to the Federal Aviation Administration (FAA) airman and medical records, the instructor held a certified flight instructor certificate with an airplane single engine land rating. He additionally held a commercial certificate with ratings for airplane single engine and multiengine land as well as instrument flight. The CFI was issued a first-class medical certificate on March 26, 2006, with no limitations.

The CFI reported that he had 760 hours total time, all of which 80 hours was amassed in the same make and model as the accident airplane. The CFI had accumulated a total of 100 hours as a flight instructor.

The student pilot stated that he had about 19 hours total flight experience all of which was accumulated with the accident CFI.

AIRCRAFT INFORMATION

The airplane was a Cessna 152, serial number 152-85286, which was manufactured in 1981. According the aircraft maintenance records and the recording tachometer in the cockpit, it had accumulated a total time in service of 2,246.3 hours. The most recent annual inspection of both the airframe and engine was recorded as completed on May 17, 2006, 20.9 hours prior to the accident.

The power plant was a Lycoming O-235-L2C, serial number RL-22006-15. Review of the maintenance records revealed a total time for the engine of 2,246.3 hours. The last major overhaul was recorded as completed on December 01, 2004, 123 hours prior to the accident.

METEOROLOGICAL INFORMATION

A routine aviation weather report (METAR) for Camarillo was issued at 1555. It stated: skies overcast 2,300 feet; visibility 10 miles; winds from 220 degrees at 6 knots; temperature 66 degrees Fahrenheit; dew point 55 degrees Fahrenheit; and an altimeter of 29.82 inHg.

The temperatures were applied to an industry Carburetor Icing Probability Chart revealing that both recorded temperatures were within the "serious icing at glide power" portion of the chart.

TESTS AND RESEARCH

Following recovery, the airplane was examined on June 20, 2006, at the storage facility of Ray's Aviation, Santa Paula, California. Present to the examination was a Safety Board investigator, an FAA inspector, and a representative of Lycoming Engines.

The airplane was intact with the engine still affixed to the firewall at its mounts. Recovery personnel had detached both wings from the fuselage at their respective inboard roots, leaving the attachment fittings of the fuel lines exposed.

The engine remained intact, with the nose landing gear displaced and lodged between the engine and firewall. Investigators preformed an external inspection of the engine, noting no anomalies. Thereafter, a precursory examination was performed. The top spark plugs were removed and inspected; the electrodes were gray in color and slightly oval, which corresponded to normal operation according to the Champion Aviation Check-A-Plug AV-27 Chart. The engine's internal mechanical continuity was established during rotation of the crankshaft (via the propeller) and upon attainment of thumb compression in all cylinders. Magneto timing was established about 20 degrees before top dead center, which was confirmed to be the appropriate timing as indicated on the data plate affixed to the engine case. The mixture arm and throttle arm were fully forward, consistent with the airplane being configured in the full rich, maximum power position. Continuity was established for both the throttle and mixture control cables, as well as the carburetor heat control cable.

Investigators removed the sump plug in the carburetor; no fuel was present. In an effort to assess the fuel line continuity, investigators poured fuel into the fuel line located on the right wing door post line near the wing root. Fuel flowed freely out of the carburetor sump. No external secretion of fluid throughout the fuel system was observed.

With the airplane still intact, aside from both wings separated from the fuselage, the Lycoming representative positioned himself in the cockpit and attempted to run the engine. The engine started without difficulty and remained at a constant 1,200 rpm for about 4 minutes. As he manipulated the throttle control in the forward position the rpm increased to about 1,750 rpm and he subsequently preformed a magneto check; no discrepancies were found. He additionally revved the engine by quickly moving the throttle control forward and aft in an effort to simulate "clearing" the throttle; again, no anomalies were noted.

After the engine was shut down, investigators disassembled the carburetor, revealing that the bowl was clean and the metal float was intact. The needle valve and seat were normal. The single piece venturi was intact and the jets were clean and clear. The fuel screen was clear.

There was no evidence of premishap mechanical malfunctions observed during the examination of the engine and airframe.

NTSB Probable Cause

a loss of engine power for undetermined reasons. A factor was the soft terrain encountered during the emergency landing.