# NTSB CEN12LA491: Grumman G-164A, N4638, Fergus Falls, MN, July 20, 2012 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: July 19, 2012, 20:00 local (Jul 20, 2012, 01:00 UTC) - Place: Fergus Falls, MN - Coordinates: 46.283889, -96.153892 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=46.2839&lon=-96.1539&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report August 13, 2013 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA/FSDO - ADs cited in the narratives: [AD 99-11-02](https://openairdocs.org/ad/99-11-02) (OpenAirDocs) - NTSB case key (mKey): 84500 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN12LA491 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/84500/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=84500 - Page: https://openairdocs.org/ntsb/CEN12LA491 ## Probable cause A total loss of engine power due to a cracked No. 2 cylinder head. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip eng cyl section](https://openairdocs.org/ntsb-findings/01058530): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Grumman G-164A, 4 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=3952704), [All aircraft, 373 cases](https://openairdocs.org/ntsb-findings/01058530/cases.md) - [Maintenance: scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010): Personnel issues › Task performance · Maintenance personnel; cases with it: [Grumman G-164A, 1 case](https://openairdocs.org/ntsb-findings/02062010/cases.md?model=3952704), [All aircraft, 320 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md) - [Inspection: scheduled/routine inspection](https://openairdocs.org/ntsb-findings/02061520): Personnel issues › Task performance · Maintenance personnel; cases with it: [Grumman G-164A, 1 case](https://openairdocs.org/ntsb-findings/02061520/cases.md?model=3952704), [All aircraft, 167 cases](https://openairdocs.org/ntsb-findings/02061520/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: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Grumman G-164A, 11 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=3952704), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) ## Analysis The pilot was spraying a large corn field when he saw a puff of white smoke come from the engine. He turned toward a road, but about half way through the turn, the engine lost all power. The pilot jettisoned the chemical load and landed in the corn field. Examination of the radial engine revealed the No. 2 cylinder head was cracked. A review of the maintenance logbooks revealed that a mandatory Federal Aviation Administration Airworthiness Directive that required a 100-hour visual inspection to prevent cylinder head cracking, had been complied with at the last annual inspection, but no entries were made that any cracks were observed. ## Factual narrative On July 17, 2012, approximately 2000 central daylight time, N4638, a Grumman G-164A airplane was substantially damaged when it made a forced landing to a corn field after a loss of engine power near Fergus Falls, Minnesota. The commercial pilot was not injured. The airplane was registered to and operated by West Central AG-AIR Incorporated, of Fergus Falls, Minnesota. Visual meteorological conditions prevailed for the agricultural aircraft operation flight conducted under 14 Code of Federal Regulations Part 137. The flight originated at the Wheaton Municipal Airport (ETH), Wheaton, Minnesota, approximately 1945. The pilot said he was on his fifth spraying pass when he saw a puff of white smoke come from the engine. He turned off the chemical sprayer and turned toward a road. About half way through the turn, the pilot observed more smoke followed by a total loss of engine power. The pilot jettisoned the chemical load and landed in the corn field. The airplane nosed-over after landing, which resulted in substantial damage to the upper wings, rudder and vertical stabilizer. A Federal Aviation Administration (FAA) Airworthiness inspector examined the Pratt & Whitney R1340 radial engine and found that the No. 2 cylinder head was cracked. A review of the maintenance logbooks revealed that FAA Airworthiness Directive 99-11-02, which required a 100-hour visual inspection of cylinder heads for cracking, was complied with at the last annual inspection. No entires were made that cracks were observed during this inspection. Further review of the logbooks revealed that the AD had not been complied with for 253 hours prior to the annual inspection. ## Aircraft - Registration: [N4638](https://openairdocs.org/deregistered/N4638-2015-05-13), registration cancelled 2015-05-13, S/N 1071, built 1973 (OpenAirDocs) - Reported make and model: GRUMMAN G-164A - Registry model: [Grumman G-164A](https://openairdocs.org/model/grumman-g-164a) (registry code 3952704) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1071 - Airframe hours: 9012 - Engines: P&W R1340 SERIES 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: West Central Ag-Air Inc - Registered owner: West Central Ag-Air Inc - Airworthiness certificate: Standard, Utility - Last inspection: Annual, March 17, 2012 - Departed: ETH, Wheaton, MN - Destination: Dumont, MN ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 41; injuries: serious; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2; last flight review April 28, 2011; seat: left; flight hours: 1,851 total, 829 in this make and model, 1,814 as pilot in command, 240 in the last 90 days, 130 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Visibility: 10 statute miles ## 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 20120719016069A](https://openairdocs.org/incident/20120719016069A), Jul 19, 2012: Grumman G-164A, Wheaton, MN, Substantial damage. Pilot was spraying corn when he saw a puff of smoke from the engine. He ceased spraying and gained altitude to assess the situation. He then witnessed… ## Other investigations on N4638 (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 DEN84LA206](https://openairdocs.org/ntsb/DEN84LA206), Jul 1, 1984: Grumman G-164A (N4638), Wyndmere, ND, substantial damage - [NTSB FTW77FPG68](https://openairdocs.org/ntsb/FTW77FPG68), Jul 21, 1977: Grumman G-164 (N4638), Keo, AR, substantial damage ## Docket (2 files) The files NTSB released with the investigation on July 22, 2013, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=84500. 962 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 892 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395659&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Record of Conversation - FAA Inspector (item 2, .PDF, 70 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40395419&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20FAA%20Inspector-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.