NTSB Factual Report

HISTORY OF FLIGHT

On February 16, 2008, about 1250 Pacific standard time, a Munson RV-6A, N154RM, experienced a loss of engine power and collided with terrain during the forced landing, approximately 1 mile south of Stanwood, Washington. The pilot operated the airplane under the provisions of Title14 Code of Federal Regulations Part 91. The private pilot and single passenger were killed, and the airplane was substantially damaged. Visual meteorological conditions prevailed, and no flight plan had been filed. The personal flight originated at the Arlington Airport, Arlington, Washington, about 1230.

The pilot was in radio communications with her husband, who was on the ground. She stated over the radio that she had "lost power" and that she was landing in a field. No additional information was relayed by the pilot. A witness reported to the sheriff that he heard a sound of an airplane approaching, saw it descending in altitude, and then heard it impact the ground. The wreckage was located in an open field, with the nose of the airplane imbedded into the ground, and the tail elevated at an angle of 45 degrees above the horizon.

PERSONNEL INFORMATION

The pilot, age 55, held a private pilot certificate for airplane single engine land issued October 14, 2000, and a third-class medical certificate issued June 12, 2006. Examination of a copy of the pilot's latest logbook revealed her total flight time was 1,154.4 hours in single engine airplanes, and 240.5 hours in the RV-6A she was flying, as of February 15, 2008. Her last biennial flight review was conducted on December 23, 2006.

AIRCRAFT INFORMATION

The two-seat, low-wing, fixed landing gear airplane, serial number 25117, was manufactured by Roger J Munson in 2000, and registered as an amateur built experimental category airplane. It was powered by an Aero Sport Power Ltd, O-320-D1A, 160 horsepower, experimental category engine. Review of the maintenance logbook records showed an annual inspection was completed June 10, 2007, at a recorded tachometer reading of 824.1. The Hobbs meter reading at the accident site was 859.2.

WRECKAGE AND IMPACT INFORMATION

The main wreckage was located in the southwestern corner of a large open field. The airplane was nosed into the earth with the tail standing up at a 45-degree angle. The wings and tail were still attached to the airframe. There was no ground scars leading up to the airplane wreckage. On scene responders reported a strong petroleum odor in the vicinity of the wreckage, and fuel on the ground under the nose and under the left wing. The fuel selector was in the "off" position and the magneto switch was in the "both" position.

On February 22, 2008, an Federal Aviation Administration (FAA) inspector and a technical representative from Textron-Lycoming Motors examined the wreckage at the Arlington Municipal Airport, Arlington, Washington. Fuel was found in the fuel system leading up to the carburetor. Fuel was in the carburetor bowl, and tested negative for water contamination. The right magneto was separated from the engine accessory section hanging by its spark plug leads, and the left magneto was observed to have rotated in its mount, precluding the engine timing from being checked. Both magnetos sparked when actuated by hand. The carburetor heat lever was trapped in the "off" position with the knob broken off in the cockpit. The airbox was crushed, however, the carb heat valve appeared to be in the off/cold position. The spark plugs were gray in color and exhibited no mechanical damage. The engine was rotated by hand utilizing the propeller, thumb compression was achieved on all 4 cylinders, and a borescope exam was performed on each cylinder, which established the mechanical continuity of the engine. Flight control continuity was established from the cockpit to all control surfaces.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy was performed on the pilot February 18, 2008, by the Snohomish County Medical Examiner. The autopsy findings include blunt force injuries to the head, neck, upper extremities, torso, and lower extremities. The report listed the specific injuries. The cause of death was listed as a result of those injuries.

Forensic toxicology was performed on specimens from the pilot by the FAA Forensic Toxicology Team CAMI, Oklahoma City, Oklahoma. The toxicology report stated that the specimens tested negative for carbon monoxide, cyanide, ethanol, and listed drugs. Ephedrine and pseudoephedrine was detected in blood.

ADDITIONAL INFORMATION

Temperature and dew point recorded at the Arlington Municipal Airport at 1255 on the day of the accident was 46 degrees Fahrenheit and 37 degrees Fahrenheit, respectively. Using a standard carburetor icing chart, these conditions would have made the carburetor susceptible to serious icing at cruise power.

NTSB Probable Cause

The pilot's failure to maintain airspeed above stall (Vs) during an emergency landing that lead to a stall and uncontrolled descent. Contributing to the accident was the loss of engine power for undetermined reasons.