Primary finding
Probable cause
The pilot’s failure to maintain adequate airspeed during an off-airport forced landing after a loss of engine power due to carburetor icing and his exceedance of the airplane’s critical angle-of-attack, which resulted in an aerodynamic stall. Contributing to the accident was the pilot’s delayed application of carburetor heat while operating in conditions conducive to carburetor icing. Contributing to the severity of both occupants’ injuries was the lack of adequate restraint.
Investigator assessment
Analysis narrative
The private pilot was conducting a personal cross-country flight with a pilot-rated passenger on board. A witness reported hearing the engine "sputter" and seeing the propeller slow as the airplane began descending toward an open field with the landing gear extended. Another witness, who was watching the airplane fly eastbound at low altitude, reported that it suddenly pitched down and impacted terrain in an approximate 45-degree, nose-down attitude, indicative of a stall. Based on the evidence, it is likely that the pilot was conducting a forced landing to the field due to a loss of engine power and subsequently failed to maintain adequate airspeed and exceeded the airplane's angle-of-attack, which resulted in the aerodynamic stall. An examination of the dry, flat field showed that it was an adequate emergency forced landing area. A postaccident examination of the airframe, engine, and propeller revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. Weather conditions at the time of the accident were conducive to carburetor icing at glide and cruise power. Although the carburetor heat control was found in the "on" position, it is possible that the pilot delayed the application of carburetor heat, which likely resulted in the formation of carburetor ice and the loss of engine power. An examination of damage to the airplane's structure showed that both the front seat and rear seat cockpit areas remained substantially intact and had provided a protective shell around both occupants during the crash sequence. Both pilot seats were equipped with a five-point lap belt and shoulder harness system. Evidence at the scene showed that the front seat pilot had been ejected from his seat during the crash sequence and had impacted the front cockpit instrument panel; however, he remained inside the cabin area. Examination of the front seat's lap belt and shoulder harness system latch, which was found unfastened, did not allow for a determination of whether the latch was unfastened, was fastened and failed, or whether it separated at the time of impact. The passenger in the rear seat remained restrained by his lap belt during the crash sequence; however, he impacted the rear cockpit instrument panel due to the failure and complete separation of his shoulder harness fitting. It is likely that the lack of adequate restraint for both occupants contributed to the severity of their injuries.
Source record
Factual narrative
HISTORY OF FLIGHT On April 19, 2014, about 1410 eastern daylight time, a Nanchang CJ-6A single-engine airplane, N594T, was substantially damaged during an off-airport forced landing near Flushing, Michigan. The pilot and the pilot rated passenger were fatally injured. The airplane was registered to Haywards Aviation; Vassar, Michigan, and was being operated by a private individual. Visual meteorological conditions (VMC) prevailed at the time of the accident and a flight plan had not been filed for the 14 Code of Federal Regulations Part 91 personal flight. The airplane had departed Tuscola Area Airport (CFS), Caro, Michigan, about 1350 and was destined for Maple Grove Airport (65G), Fowlerville, Michigan. A witness reported hearing the engine sputter and saw the propeller slow as the airplane began descending toward an open field with the landing gear extended. Another witness was watching the airplane flying eastbound at low altitude when it suddenly dropped and impacted terrain in a nose down attitude of about 45 degrees. Evidence at the accident scene showed the airplane came to rest upright about 19 feet from the initial ground scar. Witnesses called 9-1-1 emergency and several persons immediately responded to render aid to the two occupants. PERSONNEL INFORMATION Pilot The pilot, age 63, seated in the front seat, held a Federal Aviation Administration (FAA) private pilot certificate, most recently issued on March 29, 2010, with a rating in only airplane single engine land. He also held a restricted FAA third-class aviation medical certificate, which was issued on May 24, 2013, with a limitation "must wear lenses". Based on a review of copies of partial pilot logbook entries, partial aircraft logbook entries, FAA documents, and other sources, the pilot's total flight experience on April 19, 2014, was estimated as a total of 1,525 hours in all aircraft, which included about 145 hours of pilot experience in Nanchang CJ-6A airplanes. His pilot experience in the previous 90 days was estimated as about 13 hours, with all of that experience in the accident airplane. Pilot Rated Passenger The pilot rated passenger, age 49, seated in the rear seat, held an FAA private pilot certificate most recently issued on July 15, 2000, with ratings in only airplane single engine land and rotorcraft helicopter. He also held a restricted FAA third-class aviation medical certificate, which was issued on February 28, 2013, with a limitation "must wear lenses for distant, have glasses for near vision". The pilot rated passenger's personal logbooks were not available for examination by the NTSB during the course of the investigation. Based on a review of FAA documents, the pilot rated passenger's flight experience on February 28, 2013, was estimated as a total of 300 hours in all aircraft. No record was found which indicated that the pilot rated passenger had any previous pilot experience in the accident airplane or in any similar airplane. AIRCRAFT INFORMATION The low-wing, retractable tricycle landing gear, single-engine airplane, manufacturer's serial number (s/n) 3632009, was built in China, in 1983, by Nanchang Aircraft Manufacturing Corporation. It was built as a military pilot training airplane and had provisions for two pilots seated in two tandem cockpits, each with its own sliding canopy. The airplane was powered by a 285 horsepower Zhuzhou Huosai HS6A 9-cylinder carbureted radial engine, which drove a Huosai JD61 two-blade aluminum alloy controllable pitch propeller. It had a maximum takeoff weight of 3,087 pounds and a listed maximum speed of 230 miles per hour. The airplane was imported from China to the United States and in 2002 the airplane was issued an FAA airworthiness certificate in the experimental exhibition category. Based on a review of copies of selected pages of the aircraft maintenance records, the accident airplane had completed a satisfactory annual condition inspection on February 13, 2014. The flight times on that date were estimated as an aircraft total time of 2,737 hours and a total time since engine overhaul of 572 hours. The engine total time and the propeller total time could not be determined. METEOROLOGICAL INFORMATION The closest official weather reporting station was at KFNT, Flint, Michigan; located 10 miles southeast from the accident location, At 1353 the automated surface observation system at KFNT reported wind from 080 degrees at 10 knots, visibility 10 miles, clear of clouds, temperature 12 degrees Celsius (C), dew point - 1 degrees C, and an altimeter setting of 30.43 inches of mercury. The carburetor icing probability chart from FAA Special Airworthiness Information Bulletin (SAIB): CE-09-35 Carburetor Icing Prevention, June 30, 2009, shows a probability of icing at glide/cruise power at the temperature and dew point reported at the time of the accident. COMMUNICATIONS AND RADAR No record was found that showed N594T had made any radio contact with FAA air traffic control (ATC). No witnesses reported hearing any radio transmissions from N594T during the time of the accident. A postaccident review of FAA ATC radar data showed a primary only target which first appeared southwest of CFS at 1353:15.6. There was no transponder reply and no Mode-C altitude information. The radar track was not very consistent and dropped off three times. The last primary radar target was seen at 1409:35.7 near the accident location. WRECKAGE AND IMPACT INFORMATION FAA inspectors who responded to the scene reported that the airplane impacted an agricultural field on a generally easterly heading with the initial impact ground scars about 200 feet west of the north-south boundary road, and about 400 feet south of the east-west boundary road. The dimension of the field was estimated as about 3,000 feet from the boundary road on the north side of the field to the distant south edge of the field which was bordered by a tree line. The east to west dimension of the field was estimated as about 2,500 feet. There were no power lines, fences, trees, bushes, or other obstructions in the field, and there were no power lines, fences or other obstructions on either side of the road on the north side, or on either side of the road on the east side of the field. The FAA inspectors also reported that the dry flat cultivated agricultural field was an adequate emergency forced landing area. There was evidence of adequate fuel onboard, and there was a slight postimpact fuel spill, however there was no postimpact fire. The airplane came to rest with the nose of the airplane oriented about 30 degrees to the right of the eastbound direction of the main landing gear ground scars. The eastbound ground scars corresponding to the main landing gear were 10 feet 4 inches apart, were about 3 to 4 inches deep, and measured about 19 feet from the first point of impact. A 15 foot long crater corresponding to impacts from the nose gear, propeller, and engine cowing was about 24 inches wide at an initial depth of about 7 inches and ended about 11 inches deep. All portions of the accident airplane remained attached or partially attached and were observed at the scene. The rudder and elevator remained attached to their fittings and flight control continuity was confirmed. The empennage sustained substantial damage. The ailerons remained attached to their fittings and flight control continuity was confirmed. The nose gear was observed to be extended, but collapsed aft. The engine and engine mount were impact displaced down and displaced slightly left. The flap surfaces were observed in the retracted position. Both propeller blades showed evidence of some chordwise smearing in the soft dirt, however there was only a slight amount of impact damage on leading edges of both propeller blades. One propeller blade was bent aft about 45 degrees, and the other propeller blade had only a slight amount o