History of Flight
On October 4, 2012, about 0930 mountain standard time, an experimental amateur-built Wood Mustang II FB, registration N112MW, sustained substantial damage when it impacted terrain near San Manuel Airport (E77) in San Manuel, Arizona. The airplane was registered to and operated by the pilot under 14 CFR Part 91. The private pilot, sole occupant, was fatally injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight, which originated from San Manuel Airport at an undetermined time.
Witnesses at the airport reported that the pilot was on his first flight since certification. One witness, located on a taxiway approximately 2,300 feet from the approach end of runway 11, communicated with the accident pilot via handheld radio. He heard the pilot report low engine oil pressure and that he was returning to land. The pilot stated the oil pressure was 40 psi and that he needed 80 psi. The witness observed the airplane on downwind for runway 11. As the airplane was about one-half mile from the runway end, the witness saw the nose drop suddenly, then the airplane leveled off. The pilot initiated a left 180-degree turn to final with about 15 degrees of bank. As the airplane descended through about 500 feet above ground level (agl), the witness saw the landing gear extend. Shortly thereafter, the witness observed the airplane at an approximate bank angle of 90 degrees, and it descended out of sight behind a hill.
Another witness, a flight instructor flying a traffic pattern with a student, saw the accident airplane take off. He observed it flying a large arc southeast of the airport. He heard the pilot report low oil pressure of 40 psi. When asked if he had cycled the propeller, the pilot responded that he had, but the oil pressure dropped to 30 psi, so he was coming in to land. The witness immediately landed to keep the runway clear. He then observed the accident airplane in a tight final turn for runway 11 at about 300 to 400 feet agl, appearing low, slow, and as if it were stalling. He witnessed the left wing drop and the airplane go straight down. The airplane struck a ridge line approximately 0.8 miles northwest of E77.
Aircraft and Pilot Information
The pilot, age 77, held a private pilot certificate with an airplane single-engine land rating. He was issued a third-class medical certificate on December 17, 2010, with a limitation requiring glasses for near vision. He reported 1,189 total flight hours.
The experimental amateur-built airplane, serial number 963, was a two-seat, low-wing, retractable-gear model built by the pilot in 2009. It was powered by a Lycoming O-360-A1A engine, serial number L-2641-51A, rated at 180 horsepower, and equipped with a Hartzell model HC-E2YR-1BF constant-speed metal propeller.
Meteorological and Airport Information
Automated weather at E77 at 0930 reported wind from 100 degrees at 5 knots, visibility 10 statute miles, clear sky, temperature 27°C, dew point 0°C, and altimeter setting 30.24 inches of mercury. The calculated density altitude was about 5,107 feet. San Manuel Airport is a non-towered, privately owned airport with field elevation 3,272 feet msl, and one asphalt runway, 11/29 (4,207 feet long and 75 feet wide). The standard traffic pattern for runway 11 is left turns.
Wreckage and Impact
Examination by an FAA inspector revealed the airplane impacted terrain approximately eight-tenths of a mile from the approach end of runway 11. The debris path was contained within an 80-foot radius from the main wreckage, which came to rest at a heading of about 210 degrees magnetic at coordinates N32.38.922 W110 39.698. A post-impact fire consumed the left wing, engine, and cockpit area.
Examination Findings
Examination of the recovered airframe and flight control components revealed no evidence of preimpact mechanical malfunction. The engine remained partially attached to the mounting assembly and sustained thermal damage. The propeller was not attached; the spinner was crushed onto the hub, and both blades displayed chordwide scratches and twisting. One blade was twisted from mid-span root to tip, the other bent and twisted from about one-third from the outer tip. No evidence of oil lubrication deprivation or contamination was found. The turbocharger assembly, designed and installed by the pilot, showed no contamination and was unremarkable; no oil residue was observed in the exhaust system.
Medical and Pathological Information
The Pinal County Medical Examiner conducted an autopsy and determined the cause of death as blunt force injuries. Toxicology tests by the FAA's Civil Aeromedical Institute detected acetaminophen, ranitidine, salicylate, and amlodipine in the pilot's system.