# NTSB CEN17CA294: Air Tractor AT 502B, N421CA, Harrold, SD, July 26, 2017 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: July 26, 2017, 15:30 local (20:30 UTC) - Place: Harrold, SD - Coordinates: 44.514999, -99.769721 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.5150&lon=-99.7697&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) - Highest injury: Minor injuries - Injuries: 1 minor, 1 uninjured; on the ground: 1 minor - Status: Completed, report December 15, 2017 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA FSDO - NTSB case key (mKey): 95718 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN17CA294 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/95718/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=95718 - Page: https://openairdocs.org/ntsb/CEN17CA294 ## Probable cause The pilot’s improper attempt at a low-pass maneuver, which resulted in a collision with a tractor. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Object/animal/substance: ground vehicle](https://openairdocs.org/ntsb-findings/03022025): Environmental issues › Physical environment · Effect on operation (probable cause); cases with it: [Air Tractor AT-502B, 2 cases](https://openairdocs.org/ntsb-findings/03022025/cases.md?model=0390307), [All aircraft, 132 cases](https://openairdocs.org/ntsb-findings/03022025/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Air Tractor AT-502B, 19 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=0390307), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Intentional act](https://openairdocs.org/ntsb-findings/02051000): Personnel issues › Miscellaneous · Pilot (probable cause); cases with it: [Air Tractor AT-502B, 1 case](https://openairdocs.org/ntsb-findings/02051000/cases.md?model=0390307), [All aircraft, 9 cases](https://openairdocs.org/ntsb-findings/02051000/cases.md) - [Action: incorrect action selection](https://openairdocs.org/ntsb-findings/02041010): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Air Tractor AT-502B, 2 cases](https://openairdocs.org/ntsb-findings/02041010/cases.md?model=0390307), [All aircraft, 397 cases](https://openairdocs.org/ntsb-findings/02041010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Air Tractor AT-502B, 46 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=0390307), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Maneuvering-low-alt flying: Miscellaneous/other](https://openairdocs.org/ntsb-events/900) (defining event); cases with it: [Air Tractor AT-502B, 5 cases](https://openairdocs.org/ntsb-events/900/sequence.md?model=0390307), [All aircraft, 1,556 cases](https://openairdocs.org/ntsb-events/900/sequence.md) ## 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](https://openairdocs.org/aircraft/N421CA), registered now, S/N 502B-2672, built 2009 (OpenAirDocs) - Reported make and model: AIR TRACTOR INC AT 502B (B) - Registry model: [Air Tractor AT-502B](https://openairdocs.org/model/air-tractor-at-502b) (registry code 0390307) (OpenAirDocs) - Registry engine: [Pratt & Whitney Canada PT6A-34AG](https://openairdocs.org/engine/pratt-whitney-canada-pt6a-34ag) (registry code 52251, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 502B-2672 - Year 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 ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 33; injuries: none; 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 ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20170726012629A](https://openairdocs.org/incident/20170726012629A), Jul 26, 2017: Air Tractor Inc AT-502B, Harrold, SD, Substantial damage. On 7/26/2017 at 1630 an Air tractor 502B owned/registered to custom Air, inc. was involved in an accident during flight while performing 137 aerial… ## Docket (3 files) The files NTSB released with the investigation on November 9, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=95718. 1.2 MB in all. - Tractor Operator Statement (item 1, .PDF, 43 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457891&FileExtension=.PDF&FileName=Tractor%20Operator%20Statement-Master.PDF - Memo (item 2, .PDF, 95 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457890&FileExtension=.PDF&FileName=Memo-Master.PDF - Flightpath (item 3, .PDF, 1.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40457892&FileExtension=.PDF&FileName=Flightpath-Master.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.