# NTSB CEN25LA231: Grumman Acft ENG Cor-Schweizer G-164B, N8834H, Lockport, LA, July 1, 2025 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: July 1, 2025, 11:45 local (16:45 UTC) - Place: Lockport, LA · 29.59157 -90.47634 - Coordinates: 29.59157, -90.47634 - Nearby events: https://openairdocs.org/map.md?lat=29.5916&lon=-90.4763&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report August 19, 2026 - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Central Region - Parties: FAA - NTSB case key (mKey): 200448 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN25LA231 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/200448/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=200448 - Page: https://openairdocs.org/ntsb/CEN25LA231 ## Probable cause The pilot’s inadequate planning for the high density altitude conditions which resulted in reduced airplane performance, climb capability, and subsequent forced landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [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-164B, 4 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=3952802), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md) - [Temp/humidity/pressure: high density altitude](https://openairdocs.org/ntsb-findings/03031020): Environmental issues › Conditions/weather/phenomena · Contributed to outcome (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 3 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md?model=3952802), [All aircraft, 278 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md) - [Aircraft capability: climb capability](https://openairdocs.org/ntsb-findings/01061010): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 1 case](https://openairdocs.org/ntsb-findings/01061010/cases.md?model=3952802), [All aircraft, 183 cases](https://openairdocs.org/ntsb-findings/01061010/cases.md) - [Aircraft capability: maximum weight](https://openairdocs.org/ntsb-findings/01061035): Aircraft › Aircraft oper/perf/capability · Capability exceeded; cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 4 cases](https://openairdocs.org/ntsb-findings/01061035/cases.md?model=3952802), [All aircraft, 152 cases](https://openairdocs.org/ntsb-findings/01061035/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-164B, 2 cases](https://openairdocs.org/ntsb-findings/02061010/cases.md?model=3952802), [All aircraft, 114 cases](https://openairdocs.org/ntsb-findings/02061010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) (defining event); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 10 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=3952802), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md) ## Analysis The pilot reported that on the morning of the accident he flew two previous aerial application flights in the airplane without issue. The outside air temperature and humidity had increased since his first two flights, and he estimated that the temperature at the time of the accident was 93°F. The pilot sprayed a few fields while enroute to the final field and estimated that the airplane had about 35 gallons (210 lbs) of fuel and about 160 gallons (1,334 lbs) of liquid applicant in the hopper before arriving to the final field. He descended into the target field and completed one spray pass. As the airplane approached the end of the field, he increased airplane pitch but “noticed the plane not climbing as normal” despite all the engine gauges depicting normal indications. The airplane descended as it approached a highway, but the pilot did not want to dump the hopper over the highway or the adjacent bayou. The airplane cleared a set of powerlines next to the highway, landed hard in a field, and then nosed over. The airplane substantial damage to the fuselage, empennage, wings, and engine mount. Postaccident examination of the airplane did not reveal any mechanical malfunctions or failures that would have precluded normal operation. Since there were no anomalies found during the examination and the pilot confirmed that the engine gauges depicted normal indications during the flight, it is likely that the engine was operating normally at the time of the accident. Based on available information, the airplane’s weight at the time of the accident was likely near the airplane’s maximum gross weight limitation. The calculated density altitude for the accident flight was about 2,353 ft, which would have further degraded the airplane’s climb performance and ability to maintain altitude. ## Factual narrative On July 1, 2025, about 1145 central daylight time, a Grumman G-164B airplane, N8834H, was substantially damaged when it was involved in an accident near Lockport, Louisiana. The pilot received minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 137 aerial application flight. The pilot reported that on the morning of the accident he flew two previous aerial application flights in the airplane without issue. Before the first flight of the day, the airplane contained about 60 gallons (360 lbs) of fuel. The outside air temperature and humidity had increased since his first two flights and he estimated that the temperature at the time of the accident was 93°F. The pilot sprayed a few fields while enroute to the final field, and estimated that he had about 35 gallons (210 lbs) of fuel and about 160 gallons (1,334 lbs) of liquid applicant in the hopper before arriving to the final field. He descended into the target field and completed one spray pass. As he approached the end of the field, he increased airplane pitch but “noticed the plane not climbing as normal” despite all the engine gauges depicting normal indications. The airplane descended as he approached a highway, but he did not want to dump the hopper over the highway or the adjacent bayou. The airplane cleared a set of powerlines next to the highway, landed hard in a field, and then nosed over. The FAA inspector reported that the airplane came to rest inverted in a field. The fuselage and empennage sustained substantial damage. The engine remained partially attached to the firewall. The upper and lower wings remained attached to the fuselage and sustained leading edge damage. Postaccident examination revealed that the throttle, mixture, and propeller control levers remained in place and undamaged in the cockpit. The engine controls were positively traced from the cockpit, down the left side of the fuselage and through the firewall. The control ends were impact separated from their connection points on the carburetor and propeller governor. The control levers were actuated fore and aft and moved freely. The propeller control exhibited slight binding due to impact damage and bends in the control cable. When the propeller was rotated manually, normal thumb compression and suction was obtained at each cylinder. The crankshaft and all accessories rotated smoothly and freely when the propeller was rotated manually, and the crankshaft and cam ring operated normally. Postaccident examination of the airframe and engine did not reveal any mechanical malfunctions or failures that would have precluded normal operation. The most recent weight and balance calculation showed the empty weight was 4,252 lbs. A placard in the cockpit indicated that the maximum gross weight was 5,200 lbs. According to the maintenance records, the airplane’s maximum hopper capacity was increased from 2,000 lbs to 2,800 lbs in 2017 in accordance with CAM 8.10-3(e). The estimated weight of theairplane at the time of the accident was about 5,996 lbs. The reported hopper weight (1,334 lbs) was within the airplane’s special purpose load (hopper capacity) limitation of 2,800 lbs. The calculated density altitude for the accident flight was about 2,353 ft. ## Aircraft - Registration: [N8834H](https://openairdocs.org/aircraft/N8834H), registered now, S/N 1B, built 1975 (OpenAirDocs) - Reported make and model: GRUMMAN ACFT ENG COR-SCHWEIZER G-164B - Registry model: [Grumman Acft ENG Cor-Schweizer G-164B](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164b) (registry code 3952802) (OpenAirDocs) - Registry engine: [Pratt & Whitney R-985 series](https://openairdocs.org/engine/pratt-whitney-r-985-series) (registry code 52008, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1B - Year built: 1975 - Airframe hours: 8050.7 - Engines: Pratt & Whitney R1340-53H1G 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Ag Air LLC - Registered owner: Ag Air LLC - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, June 1, 2025, 5 hours before - Departed: Raceland, LA - Equipment: Angle of attack indicator ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 55; injuries: minor; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, without waivers/limitations; last flight review March 12, 2024; seat: front; restraint: 3-point; flight hours: 2,751.3 total, 2,737.6 as pilot in command, 13.7 in the last 90 days, 13.7 in the last 30 days, 5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 240° at 7 knots - Visibility: 7 statute miles - Temperature: 90 °F, dew point 75 °F - Altimeter: 30.08 inHg - Observed at: KHUM, 10 nm away - METAR: METAR KHUM 011647Z 24007KT 7SM FEW028 32/24 A3008= ## 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 20250701011769A](https://openairdocs.org/incident/20250701011769A), Jul 1, 2025: Grumman Acft Eng Cor-Schweizer G-164B, Lockport, LA, Substantial damage. Pilot stated he had already flown two loads that morning with everything operating as it should. On this his third load he approached the field as normal and… ## Docket (8 files) The files NTSB released with the investigation on August 19, 2026, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=200448. 67.2 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 3.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19611053&FileExtension=pdf&FileName=6120%20-%20Pilot_Redacted-Rel.pdf - NTSB investigation summary (item 2, PDF, 19 pages, 3.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19709402&FileExtension=pdf&FileName=NTSB%20Investigation%20Summary%20N8834H-Rel.pdf - Photos (item 3, PDF, 5 pages, 4 photos, 3.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19708370&FileExtension=pdf&FileName=Photos-Rel.pdf - FAA inspector's email (item 4, PDF, 1 page, 492 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19610569&FileExtension=pdf&FileName=FAA%20email%20-%20fuel%20and%20hopper%20loads_Redacted-Rel.pdf - Weight and balance documents (item 5, PDF, 11 pages, 6.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19708666&FileExtension=pdf&FileName=Weight%20and%20Balance%20Documents_Redacted-Rel.pdf - Density altitude calculation (item 6, PDF, 1 page, 92 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19710087&FileExtension=pdf&FileName=Density%20altitude%20calculation-Rel.pdf - Maintenance records (item 7, PDF, 17 pages, 49.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19611823&FileExtension=pdf&FileName=Mx%20logs_Redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 8, PDF, 1 page, 104 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19611704&FileExtension=pdf&FileName=NTSB%20Wreckage%20Release%20Form%20-%20N8834H_Redacted-Rel.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.