# NTSB CEN12LA513: Grumman Acft ENG Cor G-164A, N9822, La Salle, CO, August 1, 2012 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: August 1, 2012, 09:20 local (15:20 UTC) - Place: La Salle, CO - Coordinates: 40.338611, -104.667778 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.3386&lon=-104.6678&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report February 14, 2013 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA Denver FSDO - NTSB case key (mKey): 84561 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN12LA513 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/84561/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=84561 - Page: https://openairdocs.org/ntsb/CEN12LA513 ## Probable cause The loss of engine power due to the detached distributor rotor. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Ignition system: magneto/distributor](https://openairdocs.org/ntsb-findings/01057414): Aircraft › Aircraft power plant · Damaged/degraded (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 1 case](https://openairdocs.org/ntsb-findings/01057414/cases.md?model=3952801), [All aircraft, 101 cases](https://openairdocs.org/ntsb-findings/01057414/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Prior to flight: Aircraft maintenance event](https://openairdocs.org/ntsb-events/040); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 2 cases](https://openairdocs.org/ntsb-events/040/sequence.md?model=3952801), [All aircraft, 484 cases](https://openairdocs.org/ntsb-events/040/sequence.md) - [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 8 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=3952801), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Initial climb: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 10 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=3952801), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 12 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=3952801), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Post-impact: Roll over](https://openairdocs.org/ntsb-events/097); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 2 cases](https://openairdocs.org/ntsb-events/097/sequence.md?model=3952801), [All aircraft, 261 cases](https://openairdocs.org/ntsb-events/097/sequence.md) ## Analysis The pilot stated that shortly after takeoff for the aerial application flight, the airplane’s engine ”popped and banged.” The pilot decided to jettison the airplane’s load and return to land at the departure airport. However, while returning to the airport, the engine began to surge repeatedly between full power and a total loss of power, and the pilot decided to land in a nearby alfalfa field, where the airplane nosed over during the forced landing. Examination of the engine revealed that a screw that secured the distributor rotor to the brass gear had come out, which resulted in the detached rotor moving loosely inside the magneto. Internal damage to the rotor and magneto was consistent with the rotor rubbing inside of the magneto. This distributor rotor separation and subsequent movement most likely resulted in the rough running engine and the subsequent loss of engine power. ## Factual narrative On August 1, 2012, about 0920 mountain daylight time, a Grumman Aircraft Engineering Corporation G-164A airplane, N9822, was substantially damaged during a forced landing to a field after experiencing a loss of power near La Salle, Colorado. The pilot suffered minor injuries. The airplane was registered to and operated by Low Level Dusting Company, Inc., under the provisions of 14 Code of Federal Regulations Part 137, as an agricultural application flight. Day visual meteorological conditions prevailed and no flight plan was filed. At the time of the accident the airplane was departing from a private agricultural strip for a local flight. The pilot stated that shortly after takeoff he heard and felt the engine “pop and bang.” The pilot elected to return to the strip, at which time the engine experienced a complete loss of power. During the forced landing to a field of tall alfalfa, the ground roll was faster than desired and the airplane was approaching a ditch and obstacles at the end of the field. The pilot applied heavy braking and the airplane stopped abruptly and nosed over, coming to rest inverted. The outboard portion of the upper left wing separated, the engine separated from the airframe, and the vertical stabilizer was crushed. An examination of the engine revealed that a screw securing the distributor rotor to the brass gear had come out. The rotor had separated and was loose inside of the magneto. Internal damage to the rotor and magneto was consistent with the rotor rubbing inside of the magneto. Further examination of the engine and airframe revealed no anomalies. ## Aircraft - Registration: [N9822](https://openairdocs.org/deregistered/N9822-2018-01-10), registration cancelled 2018-01-10, S/N 1282, built 1974 (OpenAirDocs) - Reported make and model: GRUMMAN ACFT ENG COR 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: 1282 - Airframe hours: 7430 - Engines: P&W R-1340 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Low Level Dusting Co Inc - Registered owner: Low Level Dusting Co Inc - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, July 28, 2012 - Departed: NONE, La Salle, CO - Destination: NONE, La Salle, CO - Airport: NONE, Low Level Strip, runway 31, 2,800 × 50 ft, dirt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; injuries: minor; commercial; airplane ratings: single-engine land; medical: class 2, without waivers/limitations; last flight review July 28, 2011; seat: single; flight hours: 3,001 total, 2,600 in this make and model, 2,900 as pilot in command, 350 in the last 90 days, 150 in the last 30 days, 7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 260° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 55 °F - Altimeter: 30.12 inHg - Observed at: KGXY, 5 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 20120801015809A](https://openairdocs.org/incident/20120801015809A), Aug 1, 2012: Grumman Acft Eng Cor-Schweizer G-164A, Lasalle, CO, Substantial damage. On 8/1/2012, N9822, a Grumman ag-cat aircraft initiated off-airport landing near Lasalle, CO. Aircraft received substantial damage; airman uninjured. No… ## Other investigations on N9822 (1) 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 DEN84LA153](https://openairdocs.org/ntsb/DEN84LA153), May 18, 1984: Grumman G-164A (N9822), Wiggins, CO, substantial damage ## Docket (7 files) The files NTSB released with the investigation on December 31, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=84561. 6.7 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 714 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40378118&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Pilot's Statement (item 2, .PDF, 91 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40378111&FileExtension=.PDF&FileName=Pilot%27s%20Statement-Redacted.PDF - Examination Notes from Inspection Authority A&P Mechanic (item 3, .PDF, 12 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40378116&FileExtension=.PDF&FileName=Examination%20Notes%20from%20Inspection%20Authority%20A%26P%20Mechanic-Master.PDF - Weather Summary (item 4, .PDF, 145 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40374505&FileExtension=.PDF&FileName=Weather%20Summary-Master.PDF - Photo 1 (item 5, .PDF, 5.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40378113&FileExtension=.PDF&FileName=Photo%201-Master.PDF - Photo 2 (item 6, .PDF, 199 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40378114&FileExtension=.PDF&FileName=Photo%202-Master.PDF - Photo 3 (item 7, .PDF, 209 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40378115&FileExtension=.PDF&FileName=Photo%203-Master.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.