CEN09FA430

After a cross-country visual flight rules flight of one hour and 40 minutes, the pilot was landing at an airport with a surface elevation of 6,877 feet mean sea level. While on downwind for landing the pilot extended the landing gear and flaps, and set the engine power at 1,700 rpm. A witness at the airport heard the engine “sputtering,” then the engine failed and restarted twice before he heard the engine fail completely. The pilot executed a forced landing to a field one mile south of the airport and the airplane flipped inverted during the impact with terrain. The airplane was substantially damaged by the impact forces and the post-impact fire. The two occupants were seriously injured. The investigation revealed that adequate fuel was present, with symmetrical fire damage to both wings. The engine was tested at the manufacturer's facility and during the first start the engine started normally on the first attempt without hesitation or stumbling. The engine rpms were advanced in steps to 1200 rpm and held for five (5) minutes to stabilize. The engine throttle was advanced to full open position and held for five minutes to stabilize. The engine throttle was rapidly advanced from idle to full throttle six times. Throughout the test phase, the engine accelerated normally without any hesitation or interruption in power and demonstrated the ability to produce rated horsepower.

HISTORY OF FLIGHT On July 10, 2009, 1015 mountain daylight time, a Beech 35-A33, N4334W, lost power and attempted a forced landing in a field one mile south of the Las Vegas Municipal Airport (LVS), Las Vegas, New Mexico. A post impact fire ensued after the airplane nosed over during the forced landing. The airplane was owned and operated by a private individual, as a visual flight rules (VFR) flight, under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The airplane was substantially damaged. The pilot and one passenger were seriously injured. Visual meteorological conditions prevailed and no flight plan had been filed. The flight had originated from the St. Johns Industrial Air Park (SJN), St. Johns, Arizona, at 0735 mountain standard time and was destined for the LVS airport. The pilot had recently purchased the airplane in Arizona and was flying back to his home in Connecticut. After an overnight fuel stop at the SJN airport, he intended another fuel stop at the LVS airport before continuing eastbound. The pilot was on a downwind leg to land on the “long runway” at the LVS airport and had extended the landing gear and flaps with the engine at 1,700 revolutions per minute (RPM) as he began a descent. He did not remember the engine “failing”, but he remembered the airplane suddenly descending and then almost stalling just before impact. After the first impact, the nose gear “dug in” and the airplane flipped over on its back with an immediate post-impact fire. The pilot did not lose consciousness during the impact sequence and exited through the cabin door. The pilot reentered the burning wreckage and pulled out the unconscious passenger. A witness standing outside on the airport ramp said he saw the airplane to the west of the airport flying southbound at pattern altitude when he heard the engine “sputtering”. He heard the engine fail and restart twice before he heard the engine fail completely. When the airplane began a steep descent, the witness ran inside the airport terminal building to call 9-1-1. When the witness returned he saw a column of smoke and he drove his truck directly to the accident scene and assisted the two seriously injured occupants until emergency first responders arrived. PERSONNEL INFORMATION The pilot, age 42, held a private pilot certificate with a airplane single-engine land rating. He did not hold an instrument rating. The pilot was issued an unrestricted third-class medical certificate on December 7, 2006. The pilot completed the requirements for a biennial flight review (BFR) on May 24, 2008. The pilot’s log book was destroyed in the post impact fire and was not available during the investigation. The pilot estimated that he had a total of 195 hours of pilot experience with an estimated 25 hours of pilot experience in the accident airplane within the past 30 days. AIRCRAFT INFORMATION N4334W, serial number (S/N) CD-331, a model 35 A33, was manufactured by the Beech Aircraft Corporation in 1961. Itwas a low-wing, single engine land airplane. The airplane was originally delivered with a Continental IO-470-K engine, S/N 86031, rated at 225 horsepower. At the time of the accident it was powered by a Continental IO-470-J engine, S/N 089122, rated at 230 horsepower, driving a Hartzell 2-blade, constant speed, aluminum alloy propeller. The airplane was issued a standard airworthiness certificate on April 5, 1961, in the normal category. The airplane was registered to the owner on July 9, 2009. The airplane was configured with two seats in the cockpit area and two passenger seats in a second row. There was one cabin door next to the right front seat passenger. Each of the four seats was equipped with a seat belt with a “lift to release” type latch. The airplane was not equipped with shoulder harnesses (Because of the airplane's year of manufacture shoulder harness installation was not required). The aircraft maintenance records were destroyed in the post impact fire and were not available during the investigation. A few selected pages of recent maintenance record entries provided by an inspection authority mechanic show that the most recent annual inspection was completed on July 7, 2009, at a tachometer time of 4,931.1 hours, an aircraft total time of 8,406.1 hours, and an engine total time of 1,822.6 hours. METEOROLOGICAL INFORMATION At 1553, the automated surface observing system (ASOS) at the LVS airport, located approximately 1 miles north of the accident site, reported calm winds, visibility 10 statute miles, clear of clouds, temperature 27 degrees Celsius, dew point 07 degrees Celsius, and an altimeter setting of 30.34 inches of Mercury. The elevation of the reporting station is 6,877 feet mean sea level (MSL). The density altitude for these conditions is calculated as 9,452 feet. COMMUNICATIONS There was no record of communications with the accident airplane. AIRPORT INFORMATION The Airport/ Facility Directory, Southwest U. S., indicated that runway 14/32 at the LVS airport was 8,198 feet long and 75 feet wide. The runway surface was composed of asphalt. An additional runway 2/20 at the LVS airport was 5,004 feet long and 75 feet wide. The runway surface was composed of asphalt. WRECKAGE AND IMPACT INFORMATION The accident site was located in a dry dirt and rock field with rolling grassy terrain. The gradient from the first ground scar to the final resting location was estimated as a 6 degree down gradient. A handheld global positioning system (GPS) showed an accident site location of 35 degrees, 38 minutes, 4 seconds north latitude, and 105 degrees, 9 minutes, 8 seconds west longitude, at an estimated elevation of 6,790 feet MSL. Investigators from the Safety Board and the Federal Aviation Administration (FAA) examined the wreckage at the accident scene on July 14, 2009. The debris path from the initial impact ground scar to the main wreckage was measured on a magnetic bearing of approximately 347 degrees. All wreckage debris was foundwithin a distance of 290 feet to the northwest from the initial impact ground scar. The distance and direction from the main wreckage to the approach end of runway 02 at the LVS airport was estimated at 5,200 feet on a magnetic bearing of 16 degrees. The initial impact ground scars were consistent with landing gear impacts and continued to the northwest for a distance of approximately 35 feet. Part of one nose gear door was observed 15 feet to the left and 35 feet to the north of the first ground scar. The next ground scars began 100 feet to the northwest with intermittent ground scars continuing for 120 feet. The ground scars were absent for the next 20 feet to the point where the main wreckage was observed. The airplane came to rest inverted with the tail aligned approximately 340 degrees and the front end of the fuselage aligned approximately 160 degrees. Both wings were still connected to their respective attach points. The ailerons, flaps, elevators and rudder were still connected to their respective attach points. The cockpit, cabin area, rear fuselage, and most portions of both wings sustained thermal damage. Documentation of controls and gauge indications in the cockpit was not possible because of thermal damage that consumed most non steel components in that area. All three landing gear were observed in the extended position. The nose gear strut piston was fractured and separated just below the cylinder. The fracture surfaces of the nose gear piston showed a rough granular appearance. The exact position of the flaps could not be confirmed because of the thermal damage, but they visually appeared to be partially extended. Flight control continuity was confirmed from the forward cockpit floor to both ailerons, the elevator, and the rudder. Cable continuity was also confirmed from the cockpit floor to the elevator trim tabs. Examination of the engine revealed it was partially separated from the firewall with sections of the engine mount bent and detached. Some thermal damage was observed to the rear of the engine. The propeller remained attached to the crankshaft and the spinner had crushing damage to one side of the spinner. One propeller blade had a bend of approximately 70 degrees to the rear and the other blade had a bend of approximately 15 degrees to the rear. Examination of the airframe and flight control system components revealed no evidence of pre-impact anomalies that would have precluded normal operations. PATHOLOGICAL INFORMATION A forensic toxicology test on the pilot was not performed. TESTS AND RESEARCH Investigators from the Safety Board, FAA, Hawker Beechcraft Corporation, and Teledyne Continental Motors examined the engine at the Teledyne Continental Motors facilities in Mobile, Alabama, on October 21, 2009. The engine exhibited impact damage concentrated at the throttle body and engine mounts. The spark plugs were removed for inspection and exhibited a black sooty deposit. The cylinders were inspected with a bore scopeand there were combustion deposits present in the combustion chamber and on the piston head. There was oil and corrosion present on the cylinder bore. The cylinder head combustion chamber, intake and exhaust valve faces, piston head and cylinder bore exhibited normal operating signatures. The cylinder bore finish was steel. The magnetos as received exhibited impact damage and both had signatures of movement from the damage. The magnetos were timed to the proper (22 degree BTDC) specification. After documentation of the damage substitute parts to replace impact damaged parts were installed and the engine was prepared for installation in an engine test cell. The engine was not disassembled prior to the engine run. During installation in the test cell the engine was fitted with a test club propeller. The engine experienced a normal start on the first attempt without hesitation or stumbling in observed RPM. The engine RPM was advanced in steps to 1200 RPM and held for five (5) minutes to stabilize. The engine throttle was advanced to full open position and held for five (5) minutes to stabilize. The engine throttle was rapidly advanced from idle to full throttle six times. Throughout the test phase, the engine accelerated normally without any hesitation, stumbling or interruption in power and demonstrated the ability to produce rated horsepower. No pre-impact anomalies of the engine were observed that would have precluded normal operations. ADDITIONAL INFORMATION The airplane was equipped with 63 gallon usable capacity fuel system (70 gallon total capacity). According to the Beechcraft Debonair 35-A33 Pilot’s Operating Handbook and Airplane Flight Manual, the fuel system consisted of a 25 gallon capacity rubber fuel cell in each wing leading edge, and two auxiliary 10 gallon capacity fuel cells in the wings outboard of the wheel wells. Both auxiliary fuel cells are connected to a common port in the fuel selector valve, and both feed simultaneously when the fuel selector is set to AUX.