CHI02LA268

The airplane impacted terrain during a forced landing attempt, following a loss of engine power shortly after takeoff. A witness reported that approximately 30-40 seconds after the takeoff roll was initiated, he heard the pilot announce over the Unicom frequency, "Mayday, Mayday, my engine quit." The witness reported the airplane was about 200 feet above ground level (agl) and the left wing of the airplane was perpendicular to the ground. The witness stated the airplane was turning toward the south when it impacted a cornfield adjacent to the airport. The witness thought the pilot was attempting to return to the airport. The witness reported the pilot had problems with the aircraft engine approximately one-year prior, and had repaired the engine subsequent to a forced landing. The accident flight was the first flight since the engine repair. The engine was found seized and a teardown inspection was performed. The aft piston had seized to its cylinder as a result of a heat seizure. There was evidence another seizure event that had occurred prior to the accident flight. According to the engine manufacturer, a heat seizure is a condition that occurs when the exhaust gas temperature exceeds 1,200 degrees Fahrenheit. The resulting piston expansion exceeds the manufacturer's design tolerances and the piston seizes to the cylinder wall. The minimum temperature required for a heat seizure is reduced if the piston is contaminated during a previous seizure event and is not repaired.

History of flight

On September 3, 2002, at 1900 central daylight time, an amateur-built Rebholz Rans S-10 airplane, N92PD, piloted by a private pilot, sustained substantial damage during an in-flight collision with the terrain near Cottage Grove, Wisconsin. Visual meteorological conditions prevailed at the time of the accident. The local flight was operated under the provisions of 14 CFR Part 91 without a flight plan. The pilot was fatally injured. The flight was originating at the time of the accident.

According to a local police incident report, an acquaintance of the pilot and witness to the accident reported the pilot had told him that he was going to test-fly the airplane for the first time since a forced landing that occurred approximately one-year prior. The witness reported he saw the pilot preflight the airplane and taxi out to the departure runway, runway 27 (2,146 feet by 56 feet, dry/asphalt) at the Blackhawk Field Airport (87Y), Cottage Grove, Wisconsin. The witness stated that approximately 30-40 seconds after the takeoff roll was initiated, he heard the pilot announce over the Unicom frequency, "Mayday, Mayday, my engine quit." The witness reported the airplane was about 200 feet above ground level (agl) and the left wing of the airplane was perpendicular to the ground. The witness stated the airplane was turning toward the south when it impacted a cornfield adjacent to the airport. The witness reported he thought the pilot was attempting to return to the airport and land on runway 4 (2,953 feet by 57 feet, dry/asphalt). The witness stated the pilot had problems with the aircraft engine approximately one-year prior, and had repaired the engine subsequent to a forced landing. The witness reported the pilot had been ground-testing the engine for several weeks at several engine rpm settings.

Personnel information

The pilot held a private pilot certificate with airplane single-engine land, airplane multiengine land, and instrument airplane ratings. The Federal Aviation Administration (FAA) issued his pilot certificate on February 02, 2002.

FAA records indicate his last medical examination was completed on June 26, 2002, and that he was issued a third-class medical certificate with the limitation; "must wear corrective lenses for near and distant vision." The pilot reported having a total flight time of 600 hours, on his medical certificate application.

According to aircraft records, the pilot had accumulated about 170 hours in the accident airplane.

The pilot also held a repairman certificate for the accident airplane, which was issued by the FAA on October 27, 1995.

Aircraft information

The Rans S-10 is a single engine, mid-wing airplane. The fuselage and empennage are constructed of welded 4130 steel tubing, covered with fabric. The wings are externally braced and contain two 9-gallon metal fuel tanks. The airplane was equipped with dual controls and could accommodate two occupants. The accident airplane, serial number 0290086, had a useful load of 290 lbs and a certified maximum takeoff weight of 875 lbs.

The airplane was issued a Special Airworthiness Certificate on August 25, 1995, and was certified as an experimental category airplane. The accident airplane had accumulated a total flight time of 174.2 hours since new, according to the aircraft's hour meter and aircraft records. The last annual inspection was completed on August 26, 2002, and the airplane had accumulated 0.1 hours since the inspection.

The engine was a 65 horsepower Rotax 582, serial number 3916836. The engine had accumulated 174.2 hours since new. On August 28, 2001, at 172.5 hours total time, the engine experienced a loss of power during flight resulting in a forced landing. The aircraft records did not indicate what type of maintenance was performed on the engine subsequent to the loss of engine power. An engine maintenance logbook was not recovered.

Meteorological information

A weather observation station, located at the Dane County Regional Airport (MSN), 7 nautical miles (nm) northwest of the accident site, recorded the weather as:

At 1853: Winds calm; 10 statute mile (sm) visibility; sky clear; temperature 23 degrees Celsius; dew point of 11 degrees Celsius; altimeter 30.04 inches of mercury.

At 1932: Winds calm; 10 sm visibility; sky clear; temperature 18 degrees Celsius; dew point of 11 degrees Celsius; altimeter 30.05 inches of mercury.

Wreckage and impact information

On September 4, 2002, FAA inspectors performed an on-scene investigation. The wreckage was located approximately 240 feet from the approach end of runway 4 in a cornfield adjacent to the airport property. The smell of gasoline-type fuel was apparent around the airplane. The airplane was found nose down, impacted into the terrain. All components of the aircraft were located at the accident site. Flight control continuity was established from the cockpit controls to the individual flight control surfaces. Engine control continuity was established from the cockpit controls to the engine.

The engine was removed from the airframe and transported to Leading Edge Airfoils, Lyons, Wisconsin, for an additional examination. On October 16, 2002, a FAA inspector and an engine manufacturer's representative examined the engine.

An external visual inspection showed extensive impact damage to the oil pump, air filters, the starter housing, and both engine cylinders. One of the two carburetors was found separated from the engine. The carburetor jetting was manufacturer-supplied and the needles were positioned to the standard #3 position. The engine was seized and as a result the ignition system could not be tested. No discrepancies were noted with the gearbox assembly, lubrication system, cylinder heads, crankshaft, or crankcase. The rotary intake valve was within manufacturer timing tolerances.

No discrepancies were noted with the forward piston and lubrication was evident on the piston wall and skirts. The aft piston had evidence of two independent seizure events. When referenced to the exhaust port, the piston wall was scored at the 3, 6, 9, and 12 o'clock positions. The piston had "heat seizure" markings adjacent to the exhaust port. The piston also had "cold seizure" (thermo imbalance) markings at the 2, 5, 7, and 10 o'clock positions. No apparent damage was noted with the forward cylinder. The aft cylinder had aluminum deposits that corresponded to the previously described piston damage.

Medical and pathological information

On September 5, 2002, an autopsy was performed on the pilot at the Department of Pathology and Laboratory Medicine at the University of Wisconsin, Madison, Wisconsin.

A Forensic Toxicology Fatal Accident Report was prepared by the FAA Civil Aeromedical Institute, Oklahoma City, Oklahoma.

The toxicology results for the CFI were:

* No ethanol detected in kidney tissues

* No ethanol detected in muscle tissues

* No drugs detected in liver tissues

Tests and research

According to the engine manufacturer, a "heat seizure" is a condition that occurs when the exhaust gas temperature exceeds 1,200 degrees Fahrenheit. The resulting piston expansion exceeds the manufacturer's design tolerances and the piston seizes to the cylinder wall. A heat seizure is identified by, but not limited to, the scoring of the piston and cylinder in direct line with the exhaust port. The minimum temperature required for a heat seizure is reduced if the piston is contaminated during a previous seizure event and is not repaired.

The engine manufacturer reports a "cold seizure" can occur in three instances:

(1) The presence of air in the cooling system, resulting in hot spots throughout the engine.

(2) Attempting flight prior to the engine attaining recommended operating temperature.

(3) The cooling system does not maintain the specified temperature range.

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