CHI03LA201

The airplane was destroyed and both occupants fatally injured during a forced landing attempt to a field. A witness reported that the airplane appeared to be having engine problems prior to the accident. Other witnesses described the airplane spinning to the ground. Control system continuity was verified during the postaccident examination. Examination of the engine revealed no fuel present in the carburetors, or intake manifold. There was a tear found in the fuel pressure regulator diaphragm. However, according to an engine manufacturer's representative, a tear in the fuel pressure regulator diaphragm would result in excess fuel being pumped by the fuel pumps directly into the intake manifold of the engine.

History of flight

On July 5, 2003, at 0912 central daylight time, an amateur-built McIlraith Sea Rey, N216ST, piloted by a commercial pilot, was destroyed when it impacted the ground during an attempted forced landing near Tomah, Wisconsin. The 14 CFR Part 91 personal flight was operating in visual meteorological conditions without a flight plan. The pilot and pilot rated passenger were fatally injured. The flight originated at an undetermined time from the Bloyer Field Airport, Tomah, Wisconsin, and was en route to the La Crosse Municipal Airport, La Crosse, Wisconsin.

Witnesses to the accident reported seeing the airplane spinning to the ground. One of the witnesses reported hearing the airplane. The witness reported the airplane "sounded like it was having motor problems." The witness reported that the airplane "seemed to stall in mid-air then it cork-screwed to the ground."

Personnel information

The pilot in command held a commercial pilot certificate issued by the Federal Aviation Administration (FAA). The certificate listed airplane single engine land and instrument airplane ratings. An additional rating for single engine seaplanes was limited to private pilot privileges. The pilot also held a FAA third-class medical certificate. The examination date listed on the medical certificate was May 31, 2002. According to pilot records, the pilot had successfully completed a flight review as required by 14 CFR 61.56 on January 22, 2003. According to the pilot's flight logbook he had accumulated 755.7 hours total flight experience prior to the accident flight.

The pilot rated passenger held a commercial pilot certificate issued by the FAA. The certificate listed airplane single engine land, airplane single engine sea, airplane multiengine land and instrument airplane ratings. The pilot rated passenger also held a FAA second-class medical certificate. The examination date listed on the medical certificate was May 24, 2002. According to FAA records the pilot rated passenger had accumulated 1,305 hours of flight experience as of the date of his medical examination.

Aircraft information

The airplane was an amateur-built amphibious single-engine airplane built from a kit. The pilot and passenger constructed the airplane from the kit. A Bombardier-Rotax model 914 engine rated for 115 horsepower powered the airplane. According to the airplane kit manufacturers internet site, the airplane had a wingspan of 30 feet 10 inches, and a gross weight of 1,370 pounds. The airplane could seat two occupants in a side-by-side seating arrangement. The aluminum wing and tail structures were fabric covered.

According to aircraft maintenance records, the airplane had undergone an annual condition inspection that was completed on October 27, 2002. According to the log entry, the airplane was repaired due to damage incurred in an accident on July 23, 2001. The entry listed the total time on the airplane as 100.2 hours.

Meteorological information

The weather reporting facility located at the Sparta/Fort McCoy Airport, Sparta, Wisconsin, about 7 nautical miles west of the accident site, recorded the weather at 0955 as: Wind direction 230 degrees; Wind Speed 3 knots; Visibility 10 statute miles; Sky condition 1,400 feet scattered; Temperature 24 degrees Celsius; Dew-point 19 degrees Celsius; Barometric Pressure 29.92 inches mercury.

Wreckage and impact information

The FAA conducted an on-scene examination of the wreckage. The airplane came to rest in a field adjacent to a road. The coordinates of the accident site were determined to be 43-degrees 56.37-minutes north latitude, 90-degrees 34.68-minutes west longitude.

All major structural components of the airplane were located in the immediate area of the accident site. All flight control surfaces remained attached. Flight control continuity was confirmed at the scene. Evidence of a fuel spill was noted. Examination of the propeller blades indicated no impact damage on the leading edges of the blades.

The airplane's engine could be rotated freely and compression was confirmed on each cylinder. The turbocharger was rotated freely. The carburetors, intake manifolds, and carburetor float chambers were dry and had no evidence of residual fuel. The diaphragm type fuel pressure regulator that supplies fuel to both carburetors was disassembled and did not contain residual fuel. Examination of the rubber diaphragm revealed a 1/4-inch tear near the center where the spring seats on the diaphragm.

Medical and pathological information

An autopsy was performed on the pilot on July 6, 2003.

A Final Forensic Toxicology Fatal Accident Report for the pilot listed the following findings:

14 (mg/dL, mg/hg) ETHANOL detected in Muscle

3 (mg/dL, mg/hg) N-PROPANOL detected in Muscle

METOPROLOL detected in Liver

The report stated that the ethanol found in this case is from postmortem ethanol formation and not from the ingestion of ethanol.

N-propanol is an intermediate product in the formation or metabolism of ethanol. Metoprolol is a medication used to treat high blood pressure, and certain heart conditions.

A Final Forensic Toxicology Fatal Accident Report for the pilot-rated passenger listed no drugs found.

Tests and research

According to information provided by a service center for Bombardier-Rotax engines, a malfunction of the fuel pressure regulator would result in fuel-starvation. Discussions with a representative from the engine manufacturer regarding the fuel pressure regulator were conducted. According to the representative a breach of the fuel pressure regulator diaphragm would result in excess fuel being pumped by the fuel pumps directly into the intake manifold of the engine.

Additional information

The FAA was a party to the investigation.