CEN17CA294

NTSB accident investigation · Air Tractor AT 502B · Harrold, SD · July 26, 2017

Accident · Minor injuriesData collectionFinal report
Date
July 26, 2017, 15:30 local (20:30 UTC)
Place
Harrold, SD
Injuries
1 minor, 1 uninjured; on the ground: 1 minor
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N421CAAir Tractor AT 502B
Defining event
Maneuvering-low-alt flying: Miscellaneous/other
Weather
Visual (VMC) · Day
Status
Completed · report December 15, 2017
Report
Approved by Office Director
NTSB office
Central Region
Parties
FAA FSDO
FAA report
20170726012629A
Case key
95718

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The pilot’s improper attempt at a low-pass maneuver, which resulted in a collision with a tractor.

Findings · 4

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Object/animal/substance: ground vehicleEnvironmental issues › Physical environment · Effect on operationAir Tractor AT-502B: 2 casesAll aircraft: 132 casesProbable cause
Performance/control parameters: altitudeAircraft › Aircraft oper/perf/capability · Not attained/maintainedAir Tractor AT-502B: 19 casesAll aircraft: 1,310 casesProbable cause
Intentional actPersonnel issues › Miscellaneous · PilotAir Tractor AT-502B: 1 caseAll aircraft: 9 casesProbable cause
Action: incorrect action selectionPersonnel issues › Action/decision · PilotAir Tractor AT-502B: 2 casesAll aircraft: 397 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot of an agricultural airplane reported that he planned to apply an herbicide and test the spray system at maximum pressure at a specified airspeed. He added that a ground tractor was also in the field applying the same chemical. During the flight, he saw the tractor and passed over it between about 50 and 100 ft above ground level (agl). While spraying at 10 ft agl, he noted pressure, output, airspeed, and ground speed. At the end of the field, he climbed and made a left, 180° turn for another pass. The pilot reported that he "lost focus" outside of the airplane while looking at the spray results, and when he noticed the tractor, it was too late; the airplane's wheel collided with the tractor. Examination of the airplane revealed substantial damage to the fuselage. The tractor driver reported that he heard someone call him on the radio and that he answered the pilot on the radio and saw the airplane coming "directly at him, very low." The tractor driver heard and felt the impact and was knocked from his seat by the collision. The tractor driver then called his supervisor for help. The tractor driver added that his supervisor and another ground sprayer had been "buzzed" by the pilot before.

Factual narrative

The pilot of an agricultural airplane reported that he planned to apply a herbicide and test the spray system at maximum pressure at a specified airspeed. He added that a ground tractor was also in the field applying the same chemical. During the flight, he saw the tractor and passed over it at 50 to 100 ft. While spraying at 10 ft agl, he noted pressure, output, airspeed, and ground speed. At the end of the field, he climbed and made a left 180-degree turn for another pass. The pilot reported that he "lost focus" outside of the airplane, while looking at the spray results and when he noticed the tractor, it was too late; the airplane's wheel collided with the tractor. Examination of the airplane found substantial damage to the fuselage. The driver of the tractor reported that he heard someone call him on the radio, he answered the pilot on the radio and saw the airplane coming "directly at him, very low." The tractor operator heard and felt the impact and was knocked from his seat by the collision. The tractor driver then called his supervisor for help. The tractor driver added that his supervisor and another ground sprayer had been "buzzed" by the pilot before.

Aircraft

Registration
N421CA
Reported as
Air Tractor AT 502B (B)
Category
Airplane
Serial number
502B-2672
Built
2009
Damage
Substantial damage
Flight
Aerial application · Part 137
Operator
Custom Air Inc
Registered owner
Custom Air Inc
Airworthiness certificate
Special, Restricted (Special)
Departed
Harrold, SD
Destination
Harrold, SD

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
33
Injuries
None
Certificate
Commercial
Airplane ratings
Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Without waivers/limitations
Seat
Single

Weather

Conditions
Visual (VMC) · Day
Wind
40° at 10 knots, gusting 17
Visibility
10 statute miles
Temperature
90 °F, dew point 52 °F
Altimeter
30.06 inHg
Observed at
KPIR, 40 nm away

Docket · 3

The files NTSB released with the investigation on November 9, 2017, on NTSB’s docket system: statements, records, photos and specialists’ reports. 1.2 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.