# NTSB CEN12LA440: Grumman Acft ENG Cor-Schweizer G-164A, N6846Q, Darksville, MO, July 13, 2012 - Type: NTSB accident investigation - Classification: Accident · Fatal · Limited investigation · Final report - Date: July 13, 2012, 11:30 local (16:30 UTC) - Place: Darksville, MO - Coordinates: 39.541942, -92.587776 - Nearby events: https://openairdocs.org/map.md?lat=39.5419&lon=-92.5878&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 February 12, 2013 - Report: Approved by Office Director - NTSB office: Central Region - Parties: Kansas City FSDO - NTSB case key (mKey): 84316 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN12LA440 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/84316/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=84316 - Page: https://openairdocs.org/ntsb/CEN12LA440 ## Probable cause The pilot did not maintain clearance from a tree line at the completion of an agricultural spray run. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 10 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=3952801), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Object/animal/substance: tree(s)](https://openairdocs.org/ntsb-findings/03022020): Environmental issues › Physical environment · Response/compensation (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 1 case](https://openairdocs.org/ntsb-findings/03022020/cases.md?model=3952801), [All aircraft, 933 cases](https://openairdocs.org/ntsb-findings/03022020/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: [Grumman Acft ENG Cor-Schweizer G-164A, 5 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=3952801), [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: [Grumman Acft ENG Cor-Schweizer G-164A, 20 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=3952801), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The aerial application airplane was observed impacting a tree along the edge of the field being sprayed. Clean, freshly cut branches were noticed in the tree and freshly broken tree branch fragments were located along the impact trail. Examination of the airframe, engine and propeller did not reveal any anomalies that would have precluded normal operation. ## Factual narrative HISTORY OF FLIGHT On July 13, 2012 about 1130 central daylight time, a Grumman G-164A, N6846Q, operated by a commercial pilot, was substantially damaged during an agricultural spraying operation when it struck a tree and impacted in a field near Darksville, Missouri. A post-impact fire ensued. The pilot was fatally injured. The aerial application flight was conducted under the provisions of 14 Code of Federal Regulations Part 137 without a flight plan. Visual meteorological conditions prevailed during the flight. The local flight departed Omar N Bradley Airport (KMBY), Moberly, Missouri at an undetermined time. A witness reported that the airplane made several spray passes over a cornfield with a line of trees near the edge of the field. After the last spray pass the witness observed the airplane strike a tree. PERSONNEL INFORMATION The pilot, age 36, held a commercial pilot certificate with an airplane single-engine land and instrument rating. On June 14, 2011, the pilot was issued a third-class medical certificate. At the time of the medical examination the pilot reported having 650 hours of flight experience with 15 hours in the last six months. AIRCRAFT INFORMATION The accident airplane was a 1977 Grumman Aircraft G-164A and was equipped with a Pratt Whitney R-985 engine. The airplane was issued a restricted airworthiness certificate on September 20, 1977. ‘Maybee Air’ Limited Liability Corporation, owned by the pilot, purchased the airplane on December 25, 2011. An annual inspection was performed by the pilot on July 1, 2012. METEOROLOGICAL INFORMATION The closest weather station was at Viertel Memorial Airport (KVER), Boonville, Missouri, located about 35 nautical miles south of the accident site. The airport was equipped with an automated weather observing system (AWOS). At 1135, the KVER AWOS reported the following weather conditions: wind 250 degrees at 6 knots; visibility 10 miles; sky clear; temperature 34 degrees Celsius (C); dew point 15 degrees C; altimeter setting 30.03 inches of mercury. WRECKAGE AND IMPACT INFORMATION The accident site was located in an open field adjacent to the field being sprayed, with a line of trees separating these two fields. Fresh limb breaks were present on the highest tree between the two fields and freshly broken tree limb fragments were located on the ground between the line of trees and the accident site. All flight control surfaces were accounted for and flight control continuity was confirmed at the accident site. The engine crank case was cracked in multiple locations, which prevented rotation and continuity checks of the engine. Chordwise scoring and bending of the propeller was noted at the accident site. Examination of the airframe, engine and propeller did not reveal any anomalies that would have precluded normal operation. MEDICAL AND PATHOLOGICAL INFORMATION On July 16, 2012, an autopsy was performed on the pilot at the Boone/Callaway County Medical Examiner’s office. The cause of death wasattributed to blunt force injuries. The FAA's Civil Aeromedical Institute in Oklahoma City, Oklahoma, performed toxicology tests on the pilot. No carbon monoxide or cyanide was detected in blood, no ethanol was detected in vitreous, and no drugs were detected in the urine. ## Aircraft - Registration: [N6846Q](https://openairdocs.org/deregistered/N6846Q-2012-09-12), registration cancelled 2012-09-12, S/N 1722, built 1977 (OpenAirDocs) - Reported make and model: GRUMMAN ACFT ENG COR-SCHWEIZER G-164A - Registry model: [Grumman Acft ENG Cor-Schweizer G-164A](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164a) (registry code 3952801) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1722 - Airframe hours: 4413 - Engines: P&W R985 450 horsepower reciprocating - Damage: Substantial damage - Fire: On-Ground - Flight: Aerial application, Part 137 - Operator: Maybee Air LLC - Registered owner: Registration Pending - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, July 1, 2012 - Departed: kmby, Moberly, MO - Destination: kmby, Moberly, MO ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 36; injuries: fatal; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, without waivers/limitations; seat: single; toxicology performed; flight hours: 750 total ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 93 °F, dew point 59 °F - Altimeter: 30.03 inHg - Observed at: kver, 35 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 20120713015169A](https://openairdocs.org/incident/20120713015169A), Jul 13, 2012: Grumman Acft Eng Cor-Schweizer G-164A, Darksville, MO, Destroyed, 1 fatal. The aircraft departed mby to return to the worksite, with 80 gallons of 100LL fuel and 200 gallons of chemical on board. Density altitude at the work site at… ## Docket (5 files) The files NTSB released with the investigation on December 18, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=84316. 931 KB in all. - Memorandum of FAA provided information (item 1, .PDF, 39 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40382111&FileExtension=.PDF&FileName=Memorandum%20of%20FAA%20provided%20information-Master.PDF - Photo 1 - Accident Site (item 2, .PDF, 451 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380675&FileExtension=.PDF&FileName=Photo%201%20-%20Accident%20Site-Master.PDF - Photo 2 - Aerial view (item 3, .PDF, 202 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380677&FileExtension=.PDF&FileName=Photo%202%20-%20Aerial%20view-Master.PDF - Photo 3 - Tree strike (item 4, .PDF, 172 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380681&FileExtension=.PDF&FileName=Photo%203%20-%20Tree%20strike-Master.PDF - Toxicology report (item 5, .PDF, 66 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40380682&FileExtension=.PDF&FileName=Toxicology%20report-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.