WPR12FA316

At the end of a 3-hour-long traffic-watch flight, the pilot began to return to the departure airport. As the airplane transitioned the airspace of an adjacent airport, the engine speed dropped to idle and surged twice. The pilot performed a precautionary landing at the adjacent airport. After an uneventful landing, the pilot performed an engine run-up and more troubleshooting steps and was unable to replicate the engine problem. The pilot then decided to depart for the home airport; however, shortly after departure, the engine speed variations began again, eventually resulting in a total loss of engine power. The pilot performed a forced landing in a nearby field, where the majority of the airplane, including most of its fuel supply system, was consumed by postimpact fire. The engine sustained minimal damage, however, and postaccident examination revealed no evidence of preaccident mechanical malfunctions or failures that would have precluded normal operation.

HISTORY OF FLIGHT On July 20, 2012, about 1815 Pacific daylight time, a Cessna 182P, N640AM, collided with power lines during a forced landing near Corona, California. The certificated commercial pilot/owner was operating the airplane under the provisions of 14 Code of Federal Regulations Part 91, as an aerial observation flight. The pilot and passenger sustained serious injuries. The airplane sustained substantial damage during the accident sequence, and was subsequently consumed by post impact fire. The local flight departed Riverside Municipal Airport, Riverside, California, about 1800, with a planned destination of Corona Municipal Airport. Visual meteorological conditions prevailed, and no flight plan had been filed. The pilot was a traffic reporter, and the flight was a traffic-watch mission for a local radio station. He stated that he had previously been a full time traffic reporter, utilizing the airplane on a regular basis for such missions until November 2007. After that time, he began reporting directly from his studio, but retained the airplane for breaking news. He continued to fly traffic-watch missions once a month in order to keep the airplane active. The accident flight was one such mission. On the day of the accident, the pilot and passenger departed from Corona at 1450, and for the next 3 hours, the flight proceeded uneventfully. While returning to Corona, the engine speed dropped twice from 2,200 to approximately 1,000 rpm. The pilot performed troubleshooting steps, with no resolution, and as such, elected to land at Riverside as a precaution. After landing, he taxied to the departure end of the runway, and performed an engine run-up, which included cycling the propeller, and checking the carburetor heat and both magnetos. All checks were normal, and he was unable to replicate the problem. After discussing the anomaly with his passenger, he elected to proceed to Corona. The departure and climbout were normal, and after about 5 minutes, the engine speed again began to oscillate, followed by a loss of power sufficient to prevent the airplane from maintaining altitude. The pilot began troubleshooting procedures, and having deduced that he would not be able to reach Corona Airport, prepared for a forced landing. As the descent progressed, and they passed over a housing development, the pilot realized he would not be able to reach his intended landing point. He subsequently turned the airplane towards a field adjacent to the houses. During the final approach, the airplane struck a set of power lines, and then collided with the ground. The airplane came to rest on a heading of 280 degrees magnetic, at the end of a dirt field, about 6,500 feet east of the arrival end of runway 25 at Corona. PERSONNEL INFORMATION A review of Federal Aviation Administration (FAA) airman records revealed that the 62-year-old pilot held a commercial pilot certificate with ratings for airplane single-engine land, helicopter, and instrument airplane. Heheld an expired second-class FAA medical certificate issued in April 2, 2010, with the limitation that he possess corrective lenses that correct for near vision. The pilot reported 35,326 total hours of flight experience, 12,000 of which were in the accident airplane make and model. He stated that his last flight review was performed in the accident airplane, and took place on October 23, 2009. AIRCRAFT INFORMATION The high-wing, single-engine airplane was manufactured in 1975, and was equipped with a Continental Motors O-470-R engine, serial number 133000-6R. Maintenance records indicated that the engine was overhauled, and installed in the airplane in August 2006. At the time of the most recent annual inspection, dated August 5, 2010, the engine had accrued a total flight time of 1,609 hours since overhaul. At that time, the airframe had accrued 15,253 total flight hours. Fire damage precluded an accurate determination of the total flight time prior to the accident, however, the pilot reported a total airframe time of 15,400 hours. METEOROLOGICAL INFORMATION An automated surface weather observation at Corona was issued about 20 minutes prior to the accident. It indicated wind from 300 degrees at 13 knots; 10 miles visibility with clear skies; temperature at 32 degrees C; dew point 14 degrees C; and an altimeter setting at 29.88 inches of mercury. TESTS AND RESEARCH The airplane was recovered from the accident site, and examined by the NTSB investigator, and representatives from the FAA, Cessna Aircraft, and Continental Motors, Inc. Airframe Fire consumed the entire cabin from the empennage, through to the firewall, along with the inboard wing sections. The empennage and the outboard section of the right wing sustained minimal damage; the left wing sustained leading edge crush damage midspan to the tip. The threaded portion of the flap actuator was not visible, which the Cessna representative stated was consistent with a fully retracted flap position. With the exception of the fuel filler caps, which remained securely in place at their respective filler necks, the entire fuel supply and storage system from the bladder tanks, through to the gascolator inlet fitting, was completely consumed by fire. The gascolator sustained thermal damage and was disassembled; its screen was clear of obstruction. Engine The engine remained attached to its mounts, and sustained crush damage to the forward section of oil sump. The lower section of the number six cylinder head exhibited a similar damage, just below the rocker boss. The magnetos remained firmly attached to their mounting pads, and the spark plugs were secure at each position, with their respective leads attached. The throttle, propeller governor, mixture, and carburetor heat control cables were continuous from the cockpit controls through to their respective control arms. The top spark plugs were removed and examined. Their electrodes remained mechanically undamaged, were coated in light graydeposits, and displayed “worn out–normal” wear signatures when compared with the Champion Spark Plugs AV-27 Check-A-Plug chart. The crankshaft turned freely when rotated by hand utilizing the propeller, and cylinder compression was observed throughout. Sparks were observed at the termination of each top spark plug lead, and both magneto impulse couplings audibly triggered simultaneously. The carburetor sustained extensive thermal damage, with pink discoloration to its outer surface. Disassembly revealed that all gaskets and seals had become charred, fragmented, and thermally destroyed. The float was of the metallic type, and remained attached to the pivot arm. The propeller and hub remained attached at the crankshaft flange; both blades sustained minimal damage, and displayed similar pitch angles at the hub. A post impact examination did not reveal any anomalies with the remnants of the airframe or engine that would have precluded normal operation. Refer to the engine and airframe report included in the public docket for further details. ADDITIONAL INFORMATION A fuel receipt provided by Corona Air Ventures revealed that the airplane was serviced with the addition of 36.70 gallons of aviation gasoline at 1020. The pilot reported that at that time, the airplane (which was equipped with two wing fuel tanks of 42 gallons capacity each) was serviced to capacity.