# NTSB CEN12CA546: Air Tractor AT-502, N1021D, Hanley Falls, MN, August 14, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Data collection · Final report - Date: August 14, 2012, 16:00 local (21:00 UTC) - Place: Hanley Falls, MN - Coordinates: 44.702777, -95.719444 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.7028&lon=-95.7194&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report October 9, 2012 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA -- Minneapolis Flight Standards - NTSB case key (mKey): 84689 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN12CA546 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/84689/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=84689 - Page: https://openairdocs.org/ntsb/CEN12CA546 ## Probable cause The pilot’s failure to maintain clearance from a guy wire during an agricultural application pass. ## 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-502, 10 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=0390303), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/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-502, 7 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=0390303), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Object/animal/substance: tower/antenna (incl guy wires)](https://openairdocs.org/ntsb-findings/03022017): Environmental issues › Physical environment · Effect on operation (probable cause); cases with it: [Air Tractor AT-502, 3 cases](https://openairdocs.org/ntsb-findings/03022017/cases.md?model=0390303), [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 altitude operation/event](https://openairdocs.org/ntsb-events/220) (defining event); cases with it: [Air Tractor AT-502, 13 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=0390303), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md) - [Uncontrolled descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Air Tractor AT-502, 17 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=0390303), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot was conducting an agricultural application pass at the time of the accident. He was flying near a set of power line support poles on the edge of the field in order to establish a global positioning system reference line for subsequent application passes. He was looking to the left to maintain clearance with the support poles when he observed guy wires in his flight path. He immediately pulled up and rolled to the right; however, the left wing struck a guy wire. The airplane impacted the ground inverted, sustaining substantial damage to the fuselage, empennage, and both wings. The pilot stated that there were no failures or malfunctions associated with the airplane before the accident. He noted that making the guy wires more visible and greater awareness on his part might have prevented the accident. ## Factual narrative The pilot was conducting an agricultural application pass at the time of the accident. He was flying near a set of power line support poles on the edge of the field in order to establish a global positioning system (GPS) reference line for subsequent application passes. He was looking to the left to maintain clearance to the support poles when he observed guy wires in his flight path. He immediately pulled up and rolled to the right; however, the left wing struck a guy wire. The airplane impacted the ground inverted. The pilot stated that there were no failures or malfunctions associated with the airplane prior to the accident. He noted that making the guy wires more visible and greater awareness on his part might have prevented the accident. ## Aircraft - Registration: [N1021D](https://openairdocs.org/deregistered/N1021D-2020-01-03), registration cancelled 2020-01-03, S/N 502-0064, built 1989 (OpenAirDocs) - Reported make and model: AIR TRACTOR INC AT-502 - Registry model: [Air Tractor AT-502](https://openairdocs.org/model/air-tractor-at-502) (registry code 0390303) (OpenAirDocs) - Registry engine: [Pratt & Whitney Canada PT6A-60A](https://openairdocs.org/engine/pratt-whitney-canada-pt6a-60a) (registry code 52043, turbo-prop) (OpenAirDocs) - Category: Airplane - Serial number: 502-0064 - Airframe hours: 10575 - Engines: P&W CANADA PT6A-34AG 750 horsepower turbo prop - Damage: Substantial damage - Fire: On-Ground - Flight: Aerial application, Part 137 - Operator: Northstar Aerospray Inc - Registered owner: Northstar Aerospray Inc - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, April 2, 2012, 95 hours before - Departed: PVT, Clara City, MN - Destination: PVT, Clara City, MN - Airport: PVT, Private ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 47; injuries: minor; commercial; airplane ratings: single-engine land; medical: class 2, with waivers/limitations; last flight review September 3, 2010; seat: single; flight hours: 13,880 total, 7,497 in this make and model, 350 in the last 90 days, 181 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 90° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 70 °F, dew point 59 °F - Altimeter: 29.93 inHg - Observed at: GDB, 8 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 20120814016979A](https://openairdocs.org/incident/20120814016979A), Aug 14, 2012: Air Tractor Inc AT-502, Hanley Falls, MN, Destroyed. Pilot was making his 3rd pass on the field, but the first pass going north to south along powerlines. Pilot was lining up to make his pass when he spotted a… ## Docket (1 files) The files NTSB released with the investigation on August 22, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=84689. 509 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 509 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40375636&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-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.