NTSB Factual Report

HISTORY OF FLIGHT

On July 30, 1999, at approximately 1730 central daylight time, an Air Tractor AT502B, N5008Z, operated and piloted by an instrument rated commercial pilot, was destroyed when it impacted terrain approximately 2 miles north and 3 miles west of the city of Giltner, Nebraska. The 14 CFR Part 137 aerial application flight was not operating on a flight plan. Visual meteorological conditions prevailed at the time of the accident. The pilot received fatal injuries. The flight originated from Aurora Municipal Airport, Aurora, Nebraska, at approximately 1715.

The airplane departed from Aurora Municipal Airport at approximately 1715, loaded with a solution containing Pencap-M for aerial application. A neighbor found the airplane wreckage on 8 Road, west of D Road and telephoned 911. A Hamilton County Deputy arrived on-scene at 1739 and found the pilot fatally injured. The Deputy stated, "In speaking with [the neighbor], it was undetermined how long the plane had been on the ground prior to the 911 call."

PERSONNEL INFORMATION

The pilot had a commercial pilot rating with an instrument rating. He held a Second Class Medical Certificate dated February 5, 1999. He had a limitation stating that he must wear corrective lenses while acting as a pilot. He listed 8,349 flight hours at the date of the examination. He held a waiver of demonstrated ability for his vision. A witness stated that he saw the pilot depart with the corrective lenses on.

AIRCRAFT INFORMATION

The airplane was an Air Tractor 502B, serial number 502B-0434. The airplane had its annual inspection performed on September 29, 1998. The airplane's Hobbs meter indicated 831.4 hours.

METEOROLOGICAL INFORMATION

At 1756, the Grand Island, Nebraska observation, located 10 nautical miles on a 338 degree magnetic bearing, was: Wind 230 degrees at 6 knots; visibility 10 miles; sky condition clear; temperature 37 degrees C; dew point 22 degrees C; altimeter 29.62 inches of mercury.

At 1730, the United States Navy Observatory altitude and azimuth of the sun in Giltner, Nebraska, were 24.8 degrees and 273.5 degrees.

FLIGHT RECORDERS

The airplane contained a SATLOC installation. The installation's computer and power supply units were examined. The examination revealed the units sustained impact damage and no evidence of pre-existing power failure was found.

The installation stores the flight's track on an internal PCMCIA memory card. This memory card was found damaged. The damaged portion of the memory card could not be read or recovered.

The memory card was read and its flight track printed. The parameters of the last recorded location are: Date 990730; time 152200; speed 129.08 knots; heading 234.3 degrees; altitude 2165.68 feet above mean sea level; latitude 40.81204 degrees north; and longitude 98.1495 degrees west.

WRECKAGE AND IMPACT INFORMATION

The intersection of D Road, a north/south running road, and 8 Road, an east/west running road, was approximately 2 miles north and 3 miles west of the city of Giltner, Nebraska. The accident aircraft was found on the shoulder of 8 Road at a spot 539 feet west of D Road's west shoulder. The airplane came to rest at that spot on a 300-degree heading. The first found point of impact was 516 feet west of D Road's west shoulder and 33 inches north of 8 Road's north shoulder. Corn stalks between the initial impact point and 78 inches east of that point were cut down at an angle of 34 degrees from the horizon. That 34-degree descent angle led down to a ground impact mark similar in size to the spray boom. That ground impact mark and the descent angle had a measured initial impact heading of 270 degrees. A ground scar about the airplane's center of mass was measured in a 225 degree heading for 25 feet from the first found ground impact point to the airplane's resting point. A semicircular pattern was observed in this ground scar in a right turn from the airplane's initial 270-degree heading to its measured resting 300-degree heading within this 25-foot ground travel.

The airplane's wings were crushed downward. The fuselage was attached to the both wings but was rotated in about a 20 degree left bank attitude. The engine was attached to the fuselage by the lower engine mount components. An on scene inspection of the airplane revealed that there was continuity of all control surfaces. The inspection further revealed that there was engine continuity. The inspection found no evidence of preimpact anomalies.

The left wing had a section of its leading edge torn off. This section was found in a cornfield in 2 pieces about 270 feet from D Road's west shoulder and about 20 feet north of 8 Road's north shoulder. Part of this section exhibited a slash and a round gouge that was approximately 1/2-inch in diameter. When placed on the airplane, these section pieces mated to the missing area.

A radio tower was found with one of its guy wire cables detached from its tower mounting position. The cable was found lying across power lines, across D Road, and was lying in the cornfield in a westerly direction from its ground mooring location. The location of this mooring point was 49 feet east of D Road's west shoulder and 24 feet north of 8 Road's north shoulder. The measurement of the guy wire showed it was 335 feet in length. The cable's detached end was found frayed. All seven of the frayed cable strands showed signs of necking. The cable had a silver colored substance on its surface between 277 feet and 289 feet from the moored end. This was a 1 by 7, 7/16-inch cable.

MEDICAL AND PATHOLOGICAL INFORMATION

An autopsy was performed on the pilot by Pathology Medical Services P.C. on August 2, 1999.

A Final Forensic Toxicology Fatal Accident Report was prepared by the Federal Aviation Administration's Civil Aeromedical Institute. The report was negative.

TESTS AND RESEARCH

An Air Tractor AT502B was used for a visibility study. From where the pilot sat, pictures were taken of the visibility outside the left side of the cockpit. The area of the left wing's leading edge where it was torn was blocked by the door post. The area could be viewed if a leaning forward position or a leaning to the left position was performed. See appended photographs.

ADDITIONAL INFORMATION

The parties to the investigation included the Federal Aviation Administration and Air Tractor, Inc.

The wreckage was released to a representative of the operator.

NTSB Probable Cause

The pilot's inadequate visual lookout, and his failure to maintain clearance from the guy wire. A factor was the guy wire.