# NTSB CHI07CA209: Air Tractor AT-301, N8841S, Lignite, ND, July 15, 2007 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Data collection · Final report - Date: July 15, 2007, 10:30 local (15:30 UTC) - Place: Lignite, ND - Coordinates: 48.166667, -102.916664 - Nearby events: https://openairdocs.org/map.md?lat=48.1667&lon=-102.9167&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report October 31, 2007 - Report: Approved by Office Director - Parties: Fargo, ND FSDO - NTSB case key (mKey): 66461 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI07CA209 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/66461/pdf - Page: https://openairdocs.org/ntsb/CHI07CA209 ## Probable cause The pilot's poor in-flight planning and failure to maintain control of the airplane when he encountered his own vortex turbulence at a low altitude. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Vortex turbulence encountered, maneuvering - aerial application - in-flight planning/decision - poor, pilot in command (cause) - altitude - low, pilot in command (cause) - aircraft control - not maintained, pilot in command (cause) - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground - In flight collision with object, other - object - wire,transmission - In flight collision with terrain/water, descent - uncontrolled - terrain condition - ground - terrain condition - ditch - On ground/water collision with object, other - object - tree(s) ## Analysis The airplane contacted the ground and power lines following a loss of control during an aerial application flight. The pilot reported that prior to spraying, he circled the field four or five times waiting for traffic to clear on a nearby road. He stated he also dropped smoke to make sure the chemical would not drift toward the road. The pilot reported that during the last circle the airplane started to settle until it contacted the terrain. The airplane then bounced and contacted the power lines. The airplane settled back to the ground, and slid across a ditch and the road before coming to rest in a grove of trees. The pilot reported that the airplane most likely contacted a vortex which resulted from the circles he made around the field. In addition, the pilot reported that he did not dump the chemical load when the airplane first started to settle toward the ground. ## Factual narrative The airplane contacted the ground and power lines following a loss of control during an aerial application flight. The pilot reported that prior to spraying, he circled the field four or five times waiting for traffic to clear on a nearby road. He stated he also dropped smoke to make sure the chemical would not drift toward the road. The pilot reported that during the last circle the airplane started to settle until it contacted the terrain. The airplane then bounced and contacted the power lines. The airplane settled back to the ground, and slid across a ditch and the road before coming to rest in a grove of trees. The pilot reported that the airplane most likely contacted a vortex which resulted from the circles he made around the field. In addition, the pilot reported that he did not dump the chemical load when the airplane first started to settle toward the ground. ## Aircraft - Registration: [N8841S](https://openairdocs.org/deregistered/N8841S-2008-08-05), registration cancelled 2008-08-05, S/N 301-0212, built 1979 (OpenAirDocs) - Reported make and model: Air Tractor AT-301 - Registry model: [Air Tractor AT-301](https://openairdocs.org/model/air-tractor-at-301) (registry code 0390103) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 301-0212 - Engines: Pratt & Whitney R-1340 reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Registered owner: Northern Ag Service Inc - Airworthiness certificate: Special, Restricted (Special) - Departed: 7K5, Kenmare, ND ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 64; injuries: serious; commercial; airplane ratings: single-engine land, multi-engine land; medical: class 2; flight hours: 8,784 total, 3,099 in this make and model, 8,784 as pilot in command, 224 in the last 90 days, 185 in the last 30 days, 8 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day ## Other investigations on N8841S (2) 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. - [NTSB MIA91LA158](https://openairdocs.org/ntsb/MIA91LA158), Jun 2, 1991: Air Tractor AT-301 (N8841S), High Springs, FL, substantial damage. Probable cause: LOSS OF ENGINE POWER DUE TO DISINTEGRATION OF THE IMPELLER CAUSED BY A WORN IMPELLER BEARING. - [NTSB MIA88LA147](https://openairdocs.org/ntsb/MIA88LA147), Apr 14, 1988: Air Tractor AT-301 (N8841S), Hastings, FL, substantial damage 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.