NTSB Factual Report

On December 4, 2001, at 2215 Pacific standard time, a Cessna 172C, N1834Y, lost engine power during an aborted landing and collided with the ground off the departure end of runway 25 at the Corona Municipal Airport (AJO), Corona, California. The student pilot/owner operated the airplane under the provisions of 14 CFR Part 91; the airplane sustained substantial damage. The student pilot, a private pilot, and a passenger were not injured. Visual meteorological conditions prevailed for the cross-country flight that departed the Henderson Airport (HND), Las Vegas, Nevada, about 2100. No flight plan had been filed. The flight was scheduled to terminate at Corona.

The Safety Board Investigator-in-charge (IIC) interviewed the student pilot/owner. The student pilot indicated that there were no discrepancies noted with the airplane on the flight to HND, or on the return flight to AJO. He refueled the airplane prior to departure from HND. The student pilot further reported that he was the pilot flying the airplane; however, the other pilot was the pilot-in-command.

The student pilot, the pilot flying (PF), switched the fuel selector to the BOTH position during the descent that started at 5,500 feet over Ontario. He stated that he does not visually verify the position the fuel selector handle is in, he does it instead by "feel." On short final he noted that they were too high and coming in too fast. He initiated an aborted landing; however, when he added power the engine did not respond.

The IIC interviewed the private pilot. The private pilot stated that the student pilot was the pilot-in-command, and was flying the airplane at the time the accident occurred.

In the private pilot's written statement to the Safety Board, during an attempted go-around due to an "unsafe landing," the engine provided power to an altitude of 80 feet mean sea level, at which point the engine quit. He stated that the PF pumped the throttle several times; however, the engine would not restart. The private pilot did not indicate which pilot was manipulating the flight controls. Due to trees off the departure end of the runway, the student pilot maneuvered the airplane to the ground in order to avoid the trees. The nose wheel impacted the terrain first and was sheared off. The airplane came to an abrupt stop and came to rest upright. The private pilot stated that the approach was too fast and too high, which precipitated the aborted landing.

The private pilot further indicated that there was an altitude restriction while transiting Ontario airspace for arriving traffic, and he thought that contributed to the high approach into AJO.

In a subsequent written statement made by the private pilot, the student pilot set the airplane up for landing, and he (the private pilot) completed the prelanding checklist, which included a check of the carburetor. He also stated that he was at all times in control of the airplane in case his direct operation was required. The private pilot assumed control of the airplane after the student had landed, and the airplane made several "bounces" down the runway. He felt the proper course of action was to attempt a go-around to regain control of the airplane and make a more controlled approach for landing.

The private pilot indicated that he was told that prior to the accident, the airplane was involved in a check ride with a Federal Aviation Administration (FAA) designated examiner and experienced loss of power. He also stated that the student pilot had notified the flight instructor that the engine had lost power on three other occasions. The private pilot did not feel that he or the student pilot did anything to influence the engine-out situation.

According to the first responders, they smelled an odor of fuel, but were unable to see any fuel leaking out of the airplane. The airport manager stated he observed the airplane in a nose down attitude. When he opened the fuel caps for each wing he was able to feel fuel in both tanks. He indicated that he could not determine how much fuel was on board due to the nose down and wing low attitude of the airplane.

The IIC inspected the airframe and power plant with assistance from Teledyne Continental Motors, who was a party to the investigation. The inspection was conducted at a private hangar in Corona, on December 19, 2001. The inspection revealed that the fuel line to the gascolator was broken at the attach point, the left fuel tank was empty, and the right fuel tank contained fuel. The underside of the fuselage in the area of the fuel selector valve had been compromised during the landing.

The fuel selector handle was free spinning in its assembly. The unit was disassembled and the fuel selector handle stem was broken just above the level of the valve body. The IIC noted that the fracture surface was at a 45-degree angle, and the break area was smooth in appearance. The IIC removed the unit that houses the fuel selector from the floorboard and observed that the fuel selector valve position was selected to the left tank. The throttle, mixture, and carburetor heat controls were in the full forward position.

The IIC established mechanical continuity throughout the engine. The top spark plugs were removed. According to the Champion Aviation Check-A-Plug Chart AV-27, the spark plugs were consistent with lead fouled operation. Manual crankshaft rotation produced thumb compression in each cylinder in firing order. During manual rotation of the crankshaft, the IIC noted that the ignition leads produced spark in firing order. The carburetor was removed and inspected. The carburetor bowl was empty, and no foreign debris was inside the carburetor or associated components.

The placards on the fuel selector were worn and unreadable.

According to the aviation routine weather report (METAR) observation at the Riverside Airport, about 10 statute miles from Corona, the temperature/dew point was 45 degrees Fahrenheit/41 degrees Fahrenheit, respectively. According to the Carburetor Icing Probability Chart, the conditions were conducive to serious icing - cruise or climb power.

ADDITIONAL INFORMATION

Repeated attempts were made to gather pilot and airplane information from the student pilot/owner, with no response.

NTSB Probable Cause

a loss of engine power due to the pilot's improper use of the carburetor heat controls while in weather conditions conducive to serious carburetor icing.