# NTSB WPR20CA159: Grumman G164, N9716, Maxwell, CA, May 29, 2020 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Data collection · Final report - Date: May 29, 2020, 14:45 local (21:45 UTC) - Place: Maxwell, CA - Coordinates: 39.299446, -122.188888 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.2994&lon=-122.1889&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff-rejected takeoff: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Western Pacific Region - NTSB case key (mKey): 101352 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR20CA159 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101352/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=101352 - Page: https://openairdocs.org/ntsb/WPR20CA159 ## Probable cause The pilot's delayed decision to abort the takeoff when the airplane was not attaining sufficient airspeed for takeoff and subsequently departed the end of the runway and collided with terrain. Contributing to the accident was the pilot's inadequate preflight preparation and planning and decision to takeoff with a tailwind. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Action: delayed action](https://openairdocs.org/ntsb-findings/02041025): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 1 case](https://openairdocs.org/ntsb-findings/02041025/cases.md?model=3952801), [All aircraft, 894 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md) - [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 1 case](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=3952801), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 3 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=3952801), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Planning/preparation: performance calculations](https://openairdocs.org/ntsb-findings/02061010): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 1 case](https://openairdocs.org/ntsb-findings/02061010/cases.md?model=3952801), [All aircraft, 114 cases](https://openairdocs.org/ntsb-findings/02061010/cases.md) - [Planning/preparation: weight/balance calculations](https://openairdocs.org/ntsb-findings/02061015): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 2 cases](https://openairdocs.org/ntsb-findings/02061015/cases.md?model=3952801), [All aircraft, 110 cases](https://openairdocs.org/ntsb-findings/02061015/cases.md) - [Wind: tailwind](https://openairdocs.org/ntsb-findings/03034015): Environmental issues › Conditions/weather/phenomena · Effect on equipment (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 5 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md?model=3952801), [All aircraft, 594 cases](https://openairdocs.org/ntsb-findings/03034015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 1 case](https://openairdocs.org/ntsb-events/060/sequence.md?model=3952801), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md) - [Takeoff-rejected takeoff: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) (defining event); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 1 case](https://openairdocs.org/ntsb-events/490/sequence.md?model=3952801), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md) - [Takeoff: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 8 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=3952801), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis The pilot reported that after loading the airplane with 2000 lbs. of sulfate and topping off with fuel in preparation for the aerial application flight, he began the takeoff roll on the 2,000 ft long airstrip with a tailwind. The pilot realized that he was in trouble and needed more airspeed, so he applied full available power as there was now insufficient runway remaining to abort the takeoff and safely stop. The airplane subsequently collided with a berm at the end of the airstrip and became airborne for a short distance before the pilot forced landed the airplane in a rice field. The airplane nosed over and came to rest inverted. The wings and empennage were substantially damaged. The pilot added that he should have evaluated the weight, wind direction, and density altitude in relation to the performance capability of the airplane. The pilot reported that there were no preimpact failures or malfunctions with the airplane or engine that would have precluded normal operation. ## Factual narrative The pilot reported that after loading the airplane with 2000 lbs. of sulfate and topping off with fuel in preparation for the aerial application flight, he began the takeoff roll on the 2,000 ft long airstrip with a tailwind. The pilot realized that he was in trouble and needed more airspeed, so he applied full available power as there was now insufficient runway remaining to abort the takeoff and safely stop. The airplane subsequently collided with a berm at the end of the airstrip and became airborne for a short distance before the pilot forced landed the airplane in a rice field. The airplane nosed over and came to rest inverted. The wings and empennage were substantially damaged. The pilot added that he should have evaluated the weight, wind direction, and density altitude in relation to the performance capability of the airplane. The pilot reported that there were no preimpact failures or malfunctions with the airplane or engine that would have precluded normal operation. ## Aircraft - Registration: [N9716](https://openairdocs.org/deregistered/N9716-2022-12-31), registration cancelled 2022-12-31, S/N 1236, built 1974 (OpenAirDocs) - Reported make and model: Grumman G164 (A) - 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: 1236 - Year built: 1974 - Airframe hours: 9903.5 - Engines: Pratt & Whitney R1340 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Moller Aviation Inc - Registered owner: Moller Aviation Inc - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, May 24, 2020 - Departed: 8CL6, Maxwell, CA - Destination: 8CL6, Maxwell, CA - Airport: 8CL6, Moller, runway N, 1,700 × 75 ft, dirt - Equipment: Satellite tracking device ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 36; injuries: none; commercial; airplane ratings: single-engine land; medical: class 2, with waivers/limitations; seat: single; restraint: 4-point; flight hours: 3,593.6 total, 1,250.5 in this make and model, 3,483 as pilot in command, 300 in the last 90 days, 100 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 15 knots - Visibility: 10 statute miles - Temperature: 90 °F ## Docket (2 files) The files NTSB released with the investigation on July 9, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=101352. 595 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 386 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485200&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Accident Photo (item 2, .PDF, 208 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40485201&FileExtension=.PDF&FileName=Accident%20Photo-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.