History of Flight
On July 27, 2015, about 1724 central daylight time, a Beech M35 airplane, N9CB, was destroyed after impacting terrain near Amery, Wisconsin. The pilot and three passengers were fatally injured. The airplane was registered to and operated by St. Croix Bonanza Association LLC under 14 Code of Federal Regulations Part 91 as a personal flight. Day visual meteorological conditions prevailed; no flight plan was filed. The flight departed from New Richmond Regional Airport (RNH), New Richmond, Wisconsin, about 1716 and was destined for Voyager Village Airstrip (9WN2), Webster, Wisconsin.
The co-owner of N9CB witnessed the departure from Runway 14 at RNH and estimated the airplane became airborne about 1,700 feet down the runway, compared to a typical ground run of about 1,000 feet. He expressed concern for weight and balance after seeing four persons on board.
Air traffic control radar returns (primary only) were coincident with the departure time and direction. The aircraft tracked northeast for 7 miles from RNH, then made a right turn near the accident site. Altitude information was unavailable due to line-of-sight limitations.
Witnesses near the accident site observed maneuvering just before impact. One described a steep climb, then a circle and twist before disappearing behind trees. Another saw a nose-down attitude with wing rocking. Three others noted a spiraling descent and reported the airplane had been performing aerobatics, "tricks," or "stunts."
Personnel Information
The 44-year-old pilot held a private pilot certificate with airplane single-engine land rating and a mechanic airframe and powerplant certificate. On May 15, 2015, he was issued a Class 3 medical certificate with no restrictions. His flight records showed 368.6 total flight hours. In the 90 days before the accident, he flew 6 flights in the accident airplane, totaling an estimated 13 hours.
Aircraft Information
N9CB (s/n D-6231) was a 1959 Beechcraft M35 Bonanza equipped with a Continental Motors IO-470-C engine (s/n 71133-7-C), a 2-blade constant-speed propeller, two 25-gallon main tanks, two 10-gallon auxiliary tanks, and two 15-gallon tip tanks.
On February 7, 2015, the airplane underwent an annual inspection at an airframe total time of 6,244 hours (tachometer 4,209 hours). The engine was last overhauled on September 26, 2014, at tachometer time 4,150 hours.
Meteorological Information
At 1715, the weather station at RNH (7 miles southwest of the accident site) reported wind 150° at 9 knots, 10 miles visibility, scattered clouds at 3,100 feet AGL, temperature 29°C, dew point 20°C, and altimeter 29.94 inHg.
Wreckage and Impact Information
The airplane impacted an open wheat field in a 10° to 15° nose-down attitude with low forward velocity. A post-crash fire consumed the cabin, rear fuselage, and outboard wings to the wheel well and auxiliary tank areas.
The airplane was upright and intact, with wing leading edges compressed inward on the lower side and ballooned upward on the upper side; the right wing leading edge separated from the forward spar. Landing gear and flaps were retracted; actuators were in the up position. The elevator trim tab was neutral.
The fuel selector valve was trapped under the forward wing carry-through structure; its placard was folded around the handle, the stem was bent, and the selector was in the off position—consistent with structural deformation. Fuel lines and tanks were consumed by fire.
No flight control anomalies were found. All cables from the cockpit remained attached to controls and bellcranks. The control surfaces were attached. The airplane had a single throw-over yoke, positioned on the left.
The engine separated from the aircraft; the propeller remained attached to the crankshaft flange. The crankshaft was fractured at the crankcase entry, with 45° shear lips and cupping. Thermal damage partially melted some engine components. Impact damage deformed the camshaft drive gear and front crankcase, preventing crankshaft rotation.
Spark plugs (Champion RHM38E) showed normal wear; no fouling. Fuel injector nozzles were unobstructed. Cylinders remained attached; rocker covers showed no pre-accident anomalies. Borescope inspection revealed no piston, barrel, head, valve, or seat anomalies. The vacuum pump was separated and damaged; the rotor was fractured but vanes intact.
Examination of airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.
Medical and Pathological Information
An autopsy on July 28, 2015, by the Midwest Medical Examiner's Office (Ramsey, Minnesota) listed cause of death as blunt force injuries. FAA toxicology tests detected no tested-for drugs.
Tests and Research
An Appareo Stratus 2 GPS receiver was recovered but contained no stored flight data.
Weight and Balance
According to the co-owner, the pilot typically departed with main/auxiliary tanks full. Fueling records indicated the pilot added 23.9 gallons the day before, consistent with filling main/auxiliary tanks. Estimated weight was 3,145 pounds (full main/auxiliary fuel and driver's license weights of occupants), against a maximum takeoff weight of 3,150 pounds. That maximum weight was based on a Beryl D' Shannon Aviation Specialties tip tanks STC, which increased MTOW by 200 pounds. The STC's flight manual supplement does not provide guidance on degraded performance or changed airspeed markings for the increased weight.
Additional Information
A close friend of the pilot stated they flew together four times in the accident airplane; the pilot enjoyed and frequently performed practice stalls. The friend reported the pilot flew at low altitude several times to "test the waters," and once flew about 200 feet AGL while "buzzing" a friend's house. The friend was concerned enough that he did not want his son to fly with the pilot alone. He noted the pilot and all three passengers (whom he knew well) tended to "live life on the edge" and were not averse to high-risk activities.