NTSB Factual Report

HISTORY OF FLIGHT

On July 24, 2001, at 1346 central daylight time, an amateur-built Veith Kolb Sling Shot, N56CV, piloted by a private pilot, sustained substantial damage during a collision with the terrain while performing a forced landing near Goodview, Minnesota. Visual meteorological conditions prevailed at the time of the accident. The personal flight was operating under the provisions of 14 CFR Part 91 without a flight plan. The pilot was fatally injured. The flight departed Mankato, Minnesota, at an undetermined time and had the intended destination of Winona Municipal Airport (ONA), Winona, Minnesota.

A witness reported hearing the airplane over his residence and estimated the airplane's altitude to be approximately 150 feet. The witness stated that he heard the airplane's engine quit operating, after which the airplane turned to the right traveling out of his view. The witness reported he heard the impact of the accident, called 911, and responded to the accident site. The witness stated that when he arrived at the accident site there was fuel draining from a fuel line that was attached to a "red gas can".

Another witness reported hearing the airplane's engine quit operating and observed the airplane "gliding" over the empty field in which the accident occurred. The witness reported the airplane made a "sharp turn to the left, stalled and impacted in the field." The witness stated that when he arrived at the accident site there were approximately four to five inches of fuel remaining in the main fuel tanks. The witness reported he had removed an additional "red fuel can" from the airplane because it was inverted and fuel was draining out onto the pilot.

PERSONNEL INFORMATION

According to Federal Aviation Administration (FAA) records, the pilot was the holder of a private pilot certificate with an airplane single-engine land rating. The pilot also held a repairman certificate for the accident aircraft. FAA records show the pilot's last medical examination was completed on August 22, 2000, and the pilot was issued a third-class medical certificate with no restrictions or limitations.

The pilot's flight logbook was reviewed and the pilot's total flight times were calculated as of the last logbook entry, dated July 19, 2001. The pilot had a total flight time of 268.5 hours, all of which were in single-engine airplanes. The pilot had flown 58.3 hours during the past year. The pilot had flown 49.2 hours during the last 90 days and 17.6 hours during the last 30 days. The pilot's first flight in the accident airplane was logged on October 21, 2000, and he had logged 50.7 hours in the accident airplane as of the last logbook entry. The pilot's last flight review, as required by Federal Aviation Regulation (FAR) 61.56, was completed on November 14, 2000.

AIRCRAFT INFORMATION

The airplane was an amateur-built Veith Kolb Sling Shot, serial number SS-00-1-00025. The Kolb Sling Shot is a single engine, high-wing, pusher propeller airplane. The metal fuselage frame is fabric-covered and is equipped with a fixed-conventional landing gear. The accident airplane was configured to seat one pilot and one passenger. The accident airplane had an empty weight of 417 lbs and a maximum useful load of 433 lbs.

The airplane was issued a Special Airworthiness Certificate on November 25, 2000. The airplane had accumulated a total time of 53.6 hours as of the last airframe logbook entry, dated July 19, 2001.

The engine was a 65 horsepower Rotax 582, model 90, serial number 5306401. The engine had accumulated a total time of 53.6 hours as of the last engine logbook entry, dated July 21, 2001.

The propeller was a two-bladed, 68-inch diameter, Ivoprop with blade numbers 0031A6 & 005B6.

METEOROLOGICAL INFORMATION

A weather observation station located at the Winona Municipal Airport (ONA), about 1.3 nautical miles (nm) from the accident site on a 109.7 degree magnetic heading, recorded the weather around the time of the accident as:

Observation Time: 1337 cdt

Wind: 360 degrees magnetic at 5 knots

Visibility: 10 statute miles

Sky Condition: Sky Clear

Temperature: 28 degrees centigrade

Dew Point: 18 degrees centigrade

Pressure: 29.92 inches of mercury

Observation Time: 1358 cdt

Wind: 360 degrees magnetic at 3 knots

Visibility: 10 statute miles

Sky Condition: Sky Clear

Temperature: 27 degrees centigrade

Dew Point: 18 degrees centigrade

Pressure: 29.92 inches of mercury

WRECKAGE AND IMPACT INFORMATION

A FAA inspector conducted the on-scene portion of the investigation.

A global positioning system (GPS) receiver reported the accident site position as 44 degrees 05 minutes 5.82 seconds north latitude, 91 degrees 44 minutes 12.42 seconds west longitude. The aircraft impacted an open, level field with no obstructions. All wreckage was located within a 25 foot perimeter. The tailboom was separated from the main cabin structure and the wings remained attached to their support structure. All aircraft structural components and flight controls were identified and accounted for at the accident site. No anomalies were found with the flight control systems that could be associated with any pre-impact condition.

The fuel system was modified from the kit-supplied construction drawings. There was an external fuel port added to the rear cockpit structure with a filler tube connected to the aft-fuel tank cap. An electrical fuel pump was connected to the forward-fuel tank cap to allow fuel transfer from a third fuel tank located under the passenger seat. An additional gascolator bowl was installed prior to the carburetors. A fuel filter with a paper element was installed reverse to the direction of fuel flow, when compared to the construction drawings. The two main fuel tanks were vented through their handles using flexible tubing. The two vent lines initiating from the tank handles combined at a T-fitting and a single flexible vent line was run from the fitting down between the fuel tanks. The terminating end of the vent line was cut perpendicular to the line and was not secured. The two main fuel tanks were mounted on a metal tray lined with a flexible neoprene pad. The unsecured vent line was able to move along the bottom of the tray and make contact with the neoprene liner.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy was performed on the pilot at the Mayo Clinic, Rochester, Minnesota, on July 25, 2001.

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

The toxicology results for the pilot were:

* No Carbon Monoxide detected in Blood

* No Cyanide detected in Blood

* No Ethanol detected in Urine

* Tetrahydrocannabinol (Marijuana) detected in Blood

* 0.0016 (ug/ml, ug/g) Tetrahydrocannabinol Carboxylic Acid detected in Blood

* 0.388 (ug/ml, ug/g) Tetrahydrocannabinol Carboxylic Acid detected in Urine

TESTS AND RESEARCH

The engine was shipped to Leading Edge Airfoils, Lyons, Wisconsin, for a test run and further inspection. The engine was test run on October 16, 2001, and was witnessed by a FAA inspector and representatives of the engine manufacture. The engine was configured with the original aircraft's fuel filter, fuel pump, gascolator, and pulse pump. The original propeller was damaged during the accident and a test propeller was utilized for the test run. No carburetor jet adjustments were made prior to the test run. The engine was mounted on a test stand and started without any anomalies. The engine developed full power at 6,500 rpm during the full throttle test. Both ignition systems functioned without any anomalies.

No anomalies were found with the engine or its related systems that could be associated with any pre-impact condition.

ADDITIONAL DATA/INFORMATION

Parties to the investigation included the Federal Aviation Administration (FAA) and Kodiak Research Ltd (Rotax).

NTSB Probable Cause

The loss of engine power due to fuel starvation caused by a blocked, unsecured, fuel vent line. Contributing to the accident was the pilot's failure to maintain adequate airspeed during the forced landing which resulted in an inadvertent stall at a low altitude.