# NTSB GAA17CA469: Air Tractor AT 402, N38HT, San Angelo, TX, August 2, 2017 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: August 2, 2017, 18:35 local (23:35 UTC) - Place: San Angelo, TX - Coordinates: 31.356666, -100.499168 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=31.3567&lon=-100.4992&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report March 27, 2018 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 95749 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA17CA469 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/95749/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=95749 - Page: https://openairdocs.org/ntsb/GAA17CA469 ## Probable cause The pilot’s failure to maintain directional control during the landing roll in crosswind conditions. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Air Tractor AT-402B, 4 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=0390208), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Air Tractor AT-402B, 7 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=0390208), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Wind: crosswind](https://openairdocs.org/ntsb-findings/03034040): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Air Tractor AT-402B, 2 cases](https://openairdocs.org/ntsb-findings/03034040/cases.md?model=0390208), [All aircraft, 1,008 cases](https://openairdocs.org/ntsb-findings/03034040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Air Tractor AT-402B, 3 cases](https://openairdocs.org/ntsb-events/400/sequence.md?model=0390208), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) - [Landing: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Air Tractor AT-402B, 4 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=0390208), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Landing: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Air Tractor AT-402B, 3 cases](https://openairdocs.org/ntsb-events/060/sequence.md?model=0390208), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md) - [Landing: Landing gear collapse](https://openairdocs.org/ntsb-events/094); cases with it: [Air Tractor AT-402B, 1 case](https://openairdocs.org/ntsb-events/094/sequence.md?model=0390208), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis The pilot of the tailwheel-equipped airplane reported that, during the landing roll in crosswind conditions, the airplane began an uncommanded slow right turn. He added that he applied left brake and left rudder, but the airplane continued to turn right. Subsequently, the airplane ground looped to the right, the left main landing gear collapsed, and the left wing impacted the ground. The left wing sustained substantial damage. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. The automated weather observation system on the airport reported that, about 10 minutes after the accident, the wind was from 90° at 9 knots. The pilot landed on runway 36. ## Factual narrative The pilot of a tailwheel-equipped airplane reported that during the landing roll in crosswind conditions, the airplane began an un-commanded slow turn to the right. He added that he applied left brake and left rudder, but the airplane continued to the right. Subsequently the airplane ground looped to the right, the left main landing gear collapsed, and the left wing impacted the ground. The left wing sustained substantial damage. The pilot reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. The automated weather observation system on the airport reported, about 10 minutes after the accident, that the wind was from 90° at 9 knots. The pilot landed on runway 36. ## Aircraft - Registration: [N38HT](https://openairdocs.org/deregistered/N38HT-2023-02-04), registration cancelled 2023-02-04, S/N 402B-1011 (OpenAirDocs) - Reported make and model: AIR TRACTOR INC AT 402 (B) - Registry model: [Air Tractor AT-402B](https://openairdocs.org/model/air-tractor-at-402b) (registry code 0390208) (OpenAirDocs) - Category: Airplane - Serial number: 402B-1011 - Airframe hours: 543.3 - Engines: Pratt and Whitney PT6A-27 680 horsepower turbo prop - Damage: Substantial damage - Flight: Aerial application, Public use - Operator: Usda/Ars - Registered owner: Usda/Ars - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, November 12, 2016 - Departed: SJT, San Angelo, TX - Destination: SJT, San Angelo, TX - Airport: SJT, San Angelo Rgnl/Mathis Field, runway 36, 8,049 × 150 ft, asphalt - Equipment: ADS-B, Electronic flight bag or handheld device ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 64; injuries: none; flight instructor, airline transport, commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review June 30, 2016; seat: single; restraint: 3-point; flight hours: 6,960 total, 240 in this make and model, 6,682 as pilot in command, 88 in the last 90 days, 33 in the last 30 days, 3 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 60° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: 9,000 ft overcast - Temperature: 82 °F, dew point 66 °F - Altimeter: 30.04 inHg - Observed at: KSJT ## 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 20170802010269A](https://openairdocs.org/incident/20170802010269A), Aug 2, 2017: Air Tractor Inc AT-402B, San Angelo, TX, Substantial damage. This was a research flight related to weather modification. The aircraft had a spray system that put an electrical charge on the water as it exited the spray… ## Docket (2 files) The files NTSB released with the investigation on March 1, 2018, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=95749. 1.3 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 851 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40460446&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Accident Photo (Courtesy of FAA) (item 2, .PDF, 1 photo, 492 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40460447&FileExtension=.PDF&FileName=Accident%20Photo%20(Courtesy%20of%20FAA)-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.