History of Flight
The accident occurred on May 3, 2010, at an undetermined time, when an Aero Commander S2R, registration N5531X, impacted trees and terrain near DeWitt, Arkansas. The airplane was substantially damaged. The commercial pilot, who was the sole occupant, sustained fatal injuries. The flight was an aerial application operation conducted under 14 CFR Part 137, operated by AufderHeide Flying Service, Inc. Visual meteorological conditions prevailed. The flight originated from De Witt Municipal Airport at 1530 central standard time. The pilot was expected to land by 1630, and a search began when he did not return. The wreckage was located about 2030. No witnesses were reported.
Personnel Information
The 51-year-old pilot held a commercial pilot certificate for airplane single-engine land and a second-class medical certificate issued January 15, 2010, with the limitation that he must have available glasses for near vision. His logbook indicated 8,257 total flight hours, with approximately 650 hours in the accident airplane make and model. His most recent flight review was completed on May 25, 2009.
Aircraft Information
The airplane was a single-seat, low-wing, fixed-gear Aero Commander S2R, serial number 1731R, manufactured in 1973. It was powered by a Garrett TPE331-2-201A engine (serial number P-90252C) rated at 715 horsepower at 2,000 propeller RPM, driving a Hartzell HC-B3TN-5C three-bladed propeller. The last airframe inspection was an annual on December 12, 2009, at 10,231.2 total time airframe. The last engine inspection was a 100-hour inspection on December 13, 2009, at 5,272.1 tachometer time and 9,294.5 hours since new. The operator reported the total time airframe at the time of the accident as 10,350 hours.
Meteorological Information
Recorded data from the Stuttgart, Arkansas, automated weather station, approximately 15 miles northwest of the accident site, at 1555 indicated wind from 230 degrees at 8 knots, visibility 10 statute miles, and clear skies.
Wreckage and Impact Information
The airplane impacted trees and terrain in a heavily wooded area on a southerly heading. The left and right wings, fuselage, and empennage sustained crushing and deformation. Flight control continuity could not be verified due to the damage. The outboard sections of two of the three propeller blades were separated, and all three blades exhibited twisting and leading edge damage.
Medical and Pathological Information
An autopsy performed by the Arkansas State Crime Laboratory on May 5, 2010, attributed the pilot's cause of death to blunt force injuries. Toxicological testing conducted by the FAA Toxicology Accident Research Laboratory was negative for carbon monoxide, cyanide, and ethanol. Acetaminophen was detected in the pilot's blood at a concentration of 4.786 µg/ml.
Tests and Research
Examination of the propeller and hub assembly by Hartzell Propeller Inc. under FAA supervision revealed multiple impact marks on the spring retainer sleeve at different piston/blade angle positions. The spinner dome was separated and severely damaged, and the spinner bulkhead had multiple bends. The feather stop was intact. Two propeller blade tips were separated, and blades showed bending, twisting, and leading edge damage.
The engine was examined by Honeywell representatives under FAA supervision. Impact damage was evident. The engine gear case was separated at the compressor inlet, the propeller shaft was not free to rotate, and the power section rotated with resistance. Rotational scoring was found on the propeller shaft, sun gear bore, propeller shaft roller bearing, compressor section mainshaft, and the high-speed pinion-to-power coupling shaft. Metal spray deposits were observed on turbine stator vanes and rotor blades. No pre-impact anomalies were identified. Within the gearbox, witness marks were found on the propeller shaft lock nut and planet gear teeth, consistent with rotational contact.
The engine fuel control unit, propeller governor, and P2T2 sensor were examined at Woodward Governor Company under FAA supervision, and no pre-impact anomalies were noted.