# NTSB CEN18FA232: Air Tractor AT 502B, N2063B, Enid, OK, June 19, 2018 - Type: NTSB accident investigation - Classification: Accident · Fatal · Class 2 · Field · Final report - Date: June 19, 2018, 07:15 local (12:15 UTC) - Place: Enid, OK - Coordinates: 36.472499, -97.940277 - Nearby events: https://openairdocs.org/map.md?lat=36.4725&lon=-97.9403&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) - Highest injury: Fatal - Injuries: 1 fatal - Status: Completed - Report: Approved by Office Director - Investigation class: Class 2 - NTSB office: Central Region - Parties: FAA FSDO, Air Tractor - NTSB case key (mKey): 97527 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN18FA232 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97527/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97527 - Page: https://openairdocs.org/ntsb/CEN18FA232 ## Probable cause The pilot's failure to see and avoid a known obstacle (communications tower) during agricultural spraying operations. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [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: tower/antenna (incl guy wires)](https://openairdocs.org/ntsb-findings/03022017): Environmental issues › Physical environment · Response/compensation (probable cause); cases with it: [Air Tractor AT-502B, 3 cases](https://openairdocs.org/ntsb-findings/03022017/cases.md?model=0390307), [All aircraft, 55 cases](https://openairdocs.org/ntsb-findings/03022017/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: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) (defining event); cases with it: [Air Tractor AT-502B, 22 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=0390307), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md) - [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) ## Analysis The agricultural airplane was dispatched to apply fertilizer to a nearby field that he had fertilized the previous day. One witness observed the airplane make 8-10 passes over the field then saw the airplane fly low, pop up, and make a turn. According to the witness, the airplane ran into the guy wire of a tower and then the airplane "twisted violently…and dropped straight down." The 405-ft-tall tower was properly painted and lighted and was marked on the sectional chart. Examination of the accident site revealed that the airplane struck the top portion of the tower and impacted the ground in a near-vertical attitude. Detailed examination of the airplane and engine did not reveal any pre-impact mechanical anomalies that would preclude normal operation. Toxicology testing detected doxylamine, a potentially impairing sedating antihistamine, in the pilot's blood and urine. While the detected level was within the normally sedating range, because doxylamine undergoes postmortem redistribution, levels in postmortem blood may be elevated above antemortem levels. Therefore, whether the pilot was impaired by the sedating effects of doxylamine at the time of the accident could not be determined. Additionally, the toxicology testing identified an antidepressant, citalopram, in the tested samples. Citalopram itself is not known to cause significant impairment but major depression can significantly affect judgment, response time, and executive functioning. However, because the pilot's health care prescriber could not be identified, the extent of any potential depressive symptoms at the time of the accident could not be determined. ## Factual narrative The 405-ft tall communications tower that the airplane collided with was constructed in 1989 and was supported by unmarked steel cables. The tower location was published on the Dallas-Fort Worth area visual flight rules sectional chart current at the time of the accident and was painted and lighted in accordance with FAA Circular 70/7460-1K, titled "Obstruction Marking and Lighting." The tower is lit 24-hrs a day and painted with FAA specification paint in alternating bands. Examination of maintenance logbooks for the airplane did not reveal any anomalies or uncorrected defects. On June 19, 2018, about 0715 central daylight time, an Air Tractor 502B, N2063B, was destroyed when it was involved in an accident near Enid, Oklahoma. The pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 137 agricultural flight. According to the operator, the airplane was dispatched to apply fertilizer to a nearby field. The pilot had also applied fertilizer to that field the previous day. Preflight operations were normal and company personnel stated that the pilot was in good spirits before the flight. A witness observed the airplane make 8-10 passes over the field then saw the airplane fly low, pop up, and make a turn. According to the witness, the airplane ran into the guy wire of a tower and then "twisted violently… and dropped straight down." The Board of Medicolegal Investigations, Office of the Chief Medical Examiner, Oklahoma City, Oklahoma, performed an autopsy of the pilot. The pilot's cause of death was multiple blunt force injuries. Toxicology testing was performed at the FAA Forensic Sciences Laboratory and detected 0.149 µg/ml doxylamine in the pilot's blood specimens. It was also detected in the pilot's urine. Doxylamine is a sedating antihistamine available over the counter in cold and allergy products and is also the active ingredient in some over-the-counter sleep aids. Citalopram, a prescription antidepressant, and its metabolite, desmethylcitalopram, were detected in the pilot's blood and urine. One of the witnesses, who was driving in the vicinity, reported that he saw the airplane flying in the area, and that the weather conditions were clear. The aircraft wreckage was found in an open flat wheat field north of Enid, Oklahoma. It was located about 470 ft north of a 405-ft-tall transmission tower. According to the Federal Aviation Administration (FAA) inspector who initially responded to the accident scene, the tower company identified that the top 50 ft of the tower was missing. The tower remained standing but was later taken down by the tower company on the evening of June 19, 2018. About 50 ft of dark orange tower structure and two approximately 5/8-inch diameter guy wires were intertwined with wreckage. The wreckage and ground scars were consistent with a nose-down vertical impact. There was no horizontal ground scarring or significant debris trail leading to the wreckage. Most of the wreckagewas found collocated with the fuselage. The engine was found about 325 ft northeast of the fuselage and had separated at the "C" flange. The propeller blades were found in many pieces located throughout the debris field. Some of the propeller blades exhibited evidence of a wire strike and orange paint transfer. Examination of the airplane wreckage at the accident site did not reveal any pre-impact mechanical anomalies. Flight control continuity was confirmed from the cockpit to all flight control surfaces. Thermal marks, circular scoring, and fractured turbine blades suggested that the engine was operating under some degree of power at the time of impact. ## Aircraft - Registration: [N2063B](https://openairdocs.org/deregistered/N2063B-2018-10-15), registration cancelled 2018-10-15, S/N 502B-2800, built 2012 (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-2800 - Year built: 2012 - Airframe hours: 3044 - Engines: Pratt & Whitney PT6-34AG 750 horsepower turbo prop - Damage: Destroyed - Flight: Aerial application, Part 137 - Operator: Deterding Jim - Registered owner: Deterding Jim - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, January 17, 2018, 300 hours before - Departed: 2K1, Pond Creek, OK - Destination: 2K1, Pond Creek, OK - Equipment: Satellite tracking device ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; injuries: fatal; flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review August 31, 2016; seat: center; restraint: 5-point; toxicology performed; flight hours: 12,500 total, 3,000 in this make and model, 100 in the last 90 days, 40 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 73 °F, dew point 70 °F - Altimeter: 29.98 inHg - Observed at: END, 18 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 20180619008229A](https://openairdocs.org/incident/20180619008229A), Jun 19, 2018: Air Tractor Inc AT-502B, Enid, OK, Destroyed, 1 fatal. N2063B Air tractor aircraft involved in agricultural operations was moving from wsw to ene in steady climb hit a communications tower. Tower was 419FEET high… ## Docket (8 files) The files NTSB released with the investigation on October 9, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97527. 25.2 MB in all. - NTSB form 6120 pilot operator report CEN18FA232 (item 1, PDF, 9 pages, 3.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9634624&FileExtension=pdf&FileName=NTSB%20Form%206120%20Pilot%20Operator%20Report%20CEN18FA232_Redacted-Rel.pdf - Accident site schematics CEN18FA232 (item 2, PDF, 7 pages, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9634930&FileExtension=pdf&FileName=Accident%20Site%20Schematics%20CEN18FA232-Rel.pdf - Memorandum for the record wreckage examinations findings CEN18FA232 (item 3, PDF, 2 pages, 179 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9635173&FileExtension=pdf&FileName=Memorandum%20for%20the%20Record%20Wreckage%20Examinations%20Findings%20CEN18FA232_Redacted-Rel.pdf - Memorandum for the record witness summaries and locations in proximity to accident site CEN18FA232 (item 4, PDF, 3 pages, 347 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9955926&FileExtension=pdf&FileName=Memorandum%20for%20the%20Record%20Witness%20Summaries%20and%20Locations%20in%20Proximity%20to%20Accident%20Site%20CEN18FA232_Redacted-Rel.pdf - CEN18FA232 medical factual report (item 5, PDF, 3 pages, 223 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9635005&FileExtension=pdf&FileName=CEN18FA232%20Medical%20Factual%20Report-Rel.pdf - Enid police report CEN18FA232 (item 6, PDF, 17 pages, 18.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9956255&FileExtension=pdf&FileName=Enid%20Police%20Report%20CEN18FA232_Redacted-Rel.pdf - Toxicology report (item 7, PDF, 1 page, 168 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9635079&FileExtension=pdf&FileName=Toxicology%20Report_Redacted-Rel.pdf - NTSB certification of party form air tractor CEN18FA232 (item 8, PDF, 1 page, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9634738&FileExtension=pdf&FileName=NTSB%20Certification%20of%20Party%20Form%20Air%20Tractor%20CEN18FA232_Redacted-Rel.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.