# NTSB GAA15LA101: Air Tractor AT 502B, N120TF, Archer City, TX, May 31, 2015 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: May 31, 2015, 08:08 local (13:08 UTC) - Place: Archer City, TX - Coordinates: 33.519721, -98.656112 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.5197&lon=-98.6561&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report September 24, 2015 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: Air Tractor, Inc., Pratt & Whitney Canada Worldwide, FAA - NTSB case key (mKey): 91289 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA15LA101 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/91289/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=91289 - Page: https://openairdocs.org/ntsb/GAA15LA101 ## Probable cause The pilot’s failure to maintain adequate clearance from power transmission lines during an aerial application flight. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Air Tractor AT-502B, 16 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=0390307), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md) - [Info processing/decision: identification/recognition](https://openairdocs.org/ntsb-findings/02041510): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Air Tractor AT-502B, 7 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md?model=0390307), [All aircraft, 559 cases](https://openairdocs.org/ntsb-findings/02041510/cases.md) - [Object/animal/substance: wire](https://openairdocs.org/ntsb-findings/03022032): Environmental issues › Physical environment · Awareness of condition (probable cause); cases with it: [Air Tractor AT-502B, 15 cases](https://openairdocs.org/ntsb-findings/03022032/cases.md?model=0390307), [All aircraft, 588 cases](https://openairdocs.org/ntsb-findings/03022032/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) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering: Controlled flight into terr/obj (CFIT)](https://openairdocs.org/ntsb-events/120) (defining event); cases with it: [Air Tractor AT-502B, 3 cases](https://openairdocs.org/ntsb-events/120/sequence.md?model=0390307), [All aircraft, 1,074 cases](https://openairdocs.org/ntsb-events/120/sequence.md) ## Analysis The operator reported that the pilot was conducting an agricultural application flight when the airplane struck power transmission lines. The airplane subsequently impacted terrain about 75 ft east of a state highway. The pilot sustained serious injuries and did not remember the details of the accident. A postaccident examination of the airframe and engine revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation. It is likely that the pilot failed to maintain clearance from the transmission lines while maneuvering at a low altitude. ## Factual narrative On May 31, 2015, about 0815 central daylight time, an Air Tractor 502B airplane, N120TF, struck power transmission line wires while maneuvering five nautical miles southwest of Archer City, TX. The commercial pilot, the sole occupant in the airplane, sustained serious injuries. The airplane sustained substantial damage to the fuselage, both wings, and the empennage. The airplane was registered to the Bank of Utah Trustee and operated by Chanay Aircraft Service Inc., Wichita Falls, TX , under the provisions of 14 Code of Federal Regulations Part 137 as an agricultural aerial application flight. Visual meteorological conditions prevailed for the flight, which was not operated on a visual flight rules flight plan. The flight originated from Wichita Valley Airport (F14) at 0645. The accident site was located approximately 75 feet east of Texas State Highway 79. The terrain was flat grass pasture with short mesquite shrubs and some cactus. Chanay Aircraft Services representatives reported that the pasture was being treated with a herbicide. The pilot had already made applications on other area pastures before moving to the pasture where the accident occurred. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge on June 29, 2015, the pilot stated that he didn't remember very much from the day of the accident. The pilot reported there were no pre-impact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation. The airplane sustained substantial damage to the fuselage, both wings, and empennage. AIRCRAFT INFORMATION The single-seat, low-wing, fixed-gear airplane, was manufactured in 2007, and was powered by a Pratt and Whitney PT6A-34AG turbine engine rated at 750 horse power. The airplane was also equipped with a Hartzell three-bladed, adjustable pitch propeller. The National Transportation Safety Board Pilot/Operator aircraft accident/incident report form received from the operator revealed that the airplane's most recent annual inspection was completed in December 2014. At the time of the accident the engine and airframe time was 4,100 hours. METEOROLOGICAL INFORMATION A review of recorded data from a nearby automated weather observation station, elevation 998 feet, revealed that, at 1315, conditions were wind at 360 at 4 Knots, visibility of 10 statute miles, sky clear. WRECKAGE AND IMPACT INFORMATION A set of cross-country transmission lines were running east-west, about 500 feet north of the accident site. These lines were damaged with the top two wires being broken and laying on the roadway. The three lower wires were intact but hanging low enough to cause a hazard to traffic on the highway (at about 6 feet above the roadway). The wreckage was located on the east side of the highway in the pasture, approximately 500 feet southwest of the damaged transmission lines. The aircraft was laying upright, with the nose pointing south-southwestparallel to the highway. The aircraft sustained substantial damage to the fuselage forward of the cockpit. The wing leading edges exhibited crush damage of the leading edges and there were wing skin panels that were buckled with lines of popped rivets. The tailwheel was suspended above the ground. All the flight control surfaces and all major aircraft components were locate in the immediate vicinity of the main wreckage. Both main landing gear legs, the propeller and engine reduction gearbox, and other miscellaneous aircraft parts were located between the initial impact marks and the main wreckage. During an examination of the aircraft, continuity of all the flight controls was established. The engine was damaged in the impact. The propeller and propeller reduction gearbox were separated from the engine. This separation occurred at the engine "A" flange. Two of the three propeller blades had their tips broken off near the beginning of the debris path. Blade A displayed torsional twisting and a 90 degree bend about 12 inches from the propeller hub. Blades B and C displayed torsional twisting and bending respectively. ## Aircraft - Registration: [N120TF](https://openairdocs.org/deregistered/N120TF-2017-02-13), registration cancelled 2017-02-13, S/N 502B-2610, built 2007 (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-2610 - Year built: 2007 - Airframe hours: 4100 - Engines: P & W Canada PT6A-34AG 750 horsepower turbo prop - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Chanay Aircraft Services Inc - Registered owner: Bank Of Utah Trustee - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, December 1, 2014 - Departed: F14, WICHITA FALLS, TX - Destination: F14, WICHITA FALLS, TX - Equipment: Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 50; injuries: serious; commercial; airplane ratings: single-engine land; medical: class 2, with waivers/limitations; last flight review March 1, 2014; seat: single; restraint: 4-point; flight hours: 2,712 total, 475 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 360° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 64 °F, dew point 59 °F - Altimeter: 30.15 inHg - Observed at: KCWC, 22 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 20150531006949A](https://openairdocs.org/incident/20150531006949A), May 31, 2015: Air Tractor Inc AT-502B, Archer City, TX, Substantial damage. The accident occurred while the aircraft was spraying a pasture with herbicide to eradicate mesquite bushes. The pasture is approximately 5 miles south of… ## Docket (6 files) The files NTSB released with the investigation on September 4, 2015, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=91289. 7.6 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40431567&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Record of Phone Conversation (Pilot) (item 2, .PDF, 165 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40431568&FileExtension=.PDF&FileName=Record%20of%20Phone%20Conversation%20(Pilot)-Master.PDF - Photo 1-View of damage from left side of airplane (photo courtesy of the FAA) (item 3, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40431569&FileExtension=.PDF&FileName=Photo%201-View%20of%20damage%20from%20left%20side%20of%20airplane%20(photo%20courtesy%20of%20the%20FAA)-Master.PDF - Photo 2-View of damage from front left side of airplane (photo courtesy of the FAA) (item 4, .PDF, 1.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40431570&FileExtension=.PDF&FileName=Photo%202-View%20of%20damage%20from%20front%20left%20side%20of%20airplane%20(photo%20courtesy%20of%20the%20FAA)-Master.PDF - Photo 3-View of damaged transmission line wires (photo courtesy of the FAA) (item 5, .PDF, 699 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40431571&FileExtension=.PDF&FileName=Photo%203-View%20of%20damaged%20transmission%20line%20wires%20(photo%20courtesy%20of%20the%20FAA)-Master.PDF - Statement of Party Representatives to NTSB Investigation (Air Tractor) (item 6, .PDF, 92 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40431572&FileExtension=.PDF&FileName=Statement%20of%20Party%20Representatives%20to%20NTSB%20Investigation%20(Air%20Tractor)-Redacted.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.