# NTSB WPR09LA270: Grumman G-164A, N9723, Yerington, NV, June 18, 2009 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: June 18, 2009, 06:00 local (13:00 UTC) - Place: Yerington, NV - Coordinates: 39.013332, -119.095558 - Nearby events: https://openairdocs.org/map.md?lat=39.0133&lon=-119.0956&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed, report December 15, 2009 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 73925 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR09LA270 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/73925/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=73925 - Page: https://openairdocs.org/ntsb/WPR09LA270 ## Probable cause The pilot's failure to maintain aircraft control while maneuvering during an aerial application flight. ## 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) - [Performance/control parameters](https://openairdocs.org/ntsb-findings/01062000): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 1 case](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=3952801), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/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 control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 6 cases](https://openairdocs.org/ntsb-events/240/sequence.md?model=3952801), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) ## Analysis The pilot reported that after completing a spray run he was maneuvering for another run and rolled the wings level. The airplane experienced a loss of aileron control and settled toward the ground. The pilot still had pitch control, so he lowered the nose to maintain airspeed until he was able to regain aileron control. Prior to ground impact, the pilot attempted to flare to cushion the impact. The airplane landed hard, and during the landing roll it came to a sudden stop and nosed over. A Federal Aviation Administration inspector inspected the airplane and engine on scene. Flight control continuity was established, as well as mechanical continuity of the engine; there were no mechanical anomalies found that would have precluded normal operation. ## Factual narrative On June 18, 2009, about 0600 Pacific daylight time, a Grumman G-164A, N9723, impacted the ground while maneuvering to spray a field about 3 miles east of the Yerington Municipal Airport (O43), Yerington, Nevada. Ag Air, Inc., operated the airplane under the provisions of 14 Code of Federal Regulations Part 137, as an aerial application flight. The airplane was structurally damaged. The pilot, the sole occupant, received minor injuries. Visual meteorological conditions prevailed for the local area flight, and no flight plan had been filed. According to the pilot, he had finished spraying a section of an onion field. He made a 180-degree turn back to re-enter the onion field to spray another swath. After completing the turn and rolling wings levels, he stated that he experienced a loss of aileron control, which resulted in the airplane settling toward the ground. He reported that the airplane still had pitch control, so he attempted to lower the nose to maintain airspeed until he was able to regain aileron control. Prior to ground contact, he made an attempt to flare to cushion the impact. After the airplane landed hard, it came to a sudden stop and came to rest upside down. The operator reported that the pilot started spraying an organic insecticide on the onion field about 0530. He reported the weather conditions as 10 miles plus visibility; clear skies; no wind; and a temperature of 58 degrees Fahrenheit. A Federal Aviation Administration inspector responded to the site and was able to establish flight control continuity of the airplane, and mechanical continuity of the engine. ## Aircraft - Registration: [N9723](https://openairdocs.org/deregistered/N9723-2018-04-18), registration cancelled 2018-04-18, S/N 1239, built 1974 (OpenAirDocs) - Reported make and model: GRUMMAN 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: 1239 - Airframe hours: 8963 - Engines: Pratt and Whitney - Canada R1340-AN-1 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Ag Air Inc. - Registered owner: Robert M. Nish - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, January 16, 2009, 15 hours before - Departed: O43, Yerington, NV - Destination: O43, Yerington, NV ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 30; injuries: minor; commercial; airplane ratings: single-engine land; medical: class 2, without waivers/limitations; last flight review March 17, 2009; seat: single; flight hours: 820 total, 132 in this make and model, 770 as pilot in command, 20 in the last 90 days, 10 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 250° at 5 knots - Visibility: 10 statute miles - Lowest ceiling: 6,000 ft broken - Temperature: 57 °F - Altimeter: 29.97 inHg - Observed at: NFL, 30 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 20090618010749A](https://openairdocs.org/incident/20090618010749A), Jun 18, 2009: Scwzer G164A, Yerington, NV, Destroyed. (-23) Aircraft lost altitude and contacted the ground during turn around maneuver while engaged in aerial application. ## Other investigations on N9723 (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 OAK78DVG60](https://openairdocs.org/ntsb/OAK78DVG60), Jul 13, 1978: Grumman G-164 (N9723), Davis, CA, substantial damage ## Docket (4 files) The files NTSB released with the investigation on September 30, 2009, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=73925. 1.9 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 - Pilot (item 1, .PDF, 673 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40317072&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1%20-%20Pilot-Redacted.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 - Operator (item 2, .PDF, 945 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40317073&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1%20-%20Operator-Redacted.PDF - Pilot Statement to FAA (item 3, .PDF, 237 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40319364&FileExtension=.PDF&FileName=Pilot%20Statement%20to%20FAA-Master.PDF - Record of Conversation - M Hinzman (item 4, .PDF, 28 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40319365&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20M%20Hinzman-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.