History of Flight
On November 24, 2010, at approximately 1500 central standard time, a Cessna 172M, registration N4428Q, operated by Eagle Sky Patrol, Inc., was destroyed when it struck power lines and impacted terrain while maneuvering at low altitude about 8 miles east of Velma, Oklahoma. The aerial observation flight was conducted under 14 CFR Part 91 without a flight plan, and visual meteorological conditions prevailed. The sole occupant, the pilot, was fatally injured. The flight had originated at Ardmore (1F0), Oklahoma, around 1400, with a destination of Terrell (TRL), Texas.
According to the FAA inspector, the pilot was conducting pipeline surveillance. After landing at Ardmore for refueling, he departed to continue patrolling. A witness reported that the pilot circled an oil derrick several times, flew straight, then turned and began circling again. While circling from the south and turning back west, the nose dipped, and the airplane descended, striking power lines before ground impact. Another witness saw the airplane at about 150 feet altitude, the pilot waved back, and the engine sounded normal. The witness then heard the airplane hit the power line. Two other witnesses provided similar accounts. There was a post-impact fire. No radio communications occurred between the pilot and ground crew; the pilot used visual cues.
Crew Information
The 48-year-old pilot held a commercial pilot certificate with single/multiengine and instrument ratings, and a flight instructor certificate with instrument rating. His first-class medical certificate dated June 16, 2010, had no restrictions. His logbook was never located. The FAA inspector estimated the pilot's total flight time as 1,269.2 hours, based on an October 2010 insurance application plus hours flown for Eagle Sky Patrol and on the accident day. According to his trainer, the pilot had been flying pipeline patrols for about 4 months with no prior such experience.
Aircraft Information
N4428Q, a Cessna 172M (serial number 17261707) manufactured in 1973, was powered by a Lycoming O-320-E2D engine (serial number L-34067-22A) rated at 150 horsepower, driving a McCauley 2-blade fixed-pitch propeller. The operator stated the pilot kept the maintenance records, which were not located.
Meteorological Information
A METAR from Halliburton Field (DUC), Duncan, Oklahoma, about 20 miles west of the accident site, recorded at 1511 central standard time: wind 210 degrees at 15 knots gusting to 19 knots, visibility 10 statute miles, clear sky, temperature 27°C, dew point 12°C, altimeter 29.60 inHg.
Wreckage and Impact Information
On November 26, 2010, an FAA inspector and a Cessna representative examined the wreckage. The airplane struck 30-foot-high power lines, then impacted terrain inverted about 90 feet from the initial point of impact. Flight control continuity to the cabin was present. Elevator trim measured 10 degrees tab up; flaps were up; fuel selector on BOTH. The propeller exhibited S-bending and chordwise scratches on the cambered surface.
Medical and Pathological Information
An autopsy on November 28, 2010, by the Oklahoma State Medical Examiner's Office attributed death to multiple blunt force trauma. Toxicological tests by the state office and CAMI detected ethanol in blood (0.03%) and muscle, with less than 5% carbon monoxide saturation. CAMI noted putrefaction of specimens. Acetaminophen (2.429 ug/ml, ug/g) was found in blood (cavity).
Additional Information
A friend who trained the pilot for this job stated the pilot had been flying for Eagle Sky Patrol about 4 months. Though a flight instructor, he had no previous pipeline patrol experience. Witnesses told the friend the pilot was circling a pipeline leak to guide a ground crew. The friend reported that after four tight circles, on the fifth, the pilot rolled into a hard left turn, the aircraft stalled, rolled inverted, and fell, striking power lines. The friend commented on the risks of multiple tight circles, vortex turbulence, divided attention, and gusty winds.