# NTSB ERA22LA297: Grumman G-164A, N8923H, Hopewell Township, NJ, July 2, 2022 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: July 2, 2022, 09:44 local (13:44 UTC) - Place: Hopewell Township, NJ · In field behind 2 Cassidy Court, Bridgeton, NJ - Coordinates: 39.446364, -75.279261 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.4464&lon=-75.2793&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: FAA/FSDO - NTSB case key (mKey): 105421 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA22LA297 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/105421/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=105421 - Page: https://openairdocs.org/ntsb/ERA22LA297 ## Probable cause A partial loss of engine power while maneuvering at low altitude due to a failure of the airplane’s supercharger. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip eng supercharger](https://openairdocs.org/ntsb-findings/01058560): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 3 cases](https://openairdocs.org/ntsb-findings/01058560/cases.md?model=3952801), [All aircraft, 12 cases](https://openairdocs.org/ntsb-findings/01058560/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: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) (defining event); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 7 cases](https://openairdocs.org/ntsb-events/340/sequence.md?model=3952801), [All aircraft, 820 cases](https://openairdocs.org/ntsb-events/340/sequence.md) - [Maneuvering-low-alt flying: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 20 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=3952801), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot was performing an aerial application flight over a nursery. As he pulled up at the end of a pass, he crossed over an area of trees and heard a “loud bang.” He attempted to maneuver the airplane to land in an open field; however, the airplane “ran out of altitude and airspeed” and impacted the ground, which resulted in substantial damage to the fuselage and wings. Postaccident examination of the airplane’s vintage radial engine revealed that when rotating the propeller, the drivetrain would rotate freely, and no binding was noted. All the engine cylinders were intact. The supercharger impeller was intact, but further examination revealed that it was not rotating when the propeller was moved by hand. The rear accessory/diffuser housing was removed to expose the supercharger impeller and no damage was noted on the external impeller blades; however, the rear splined impeller shaft ball bearing spacer and supercharger impeller splines were found to have sheared, allowing the impeller to freewheel. Based on this information, it is likely that the failure of the supercharger resulted in at least a partial loss of engine power, and that the failure occurred while the pilot was performing a low altitude maneuver. The pilot was subsequently unable to recover from the resulting loss of airspeed before the airplane impacted the ground. ## Factual narrative On July 2, 2022, about 0944 eastern daylight time, a Grumman G-164A, N8923H was substantially damaged when it was involved in an accident in Hopewell Township, New Jersey. The pilot was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 137 aerial application flight. The pilot was performing an aerial application flight over a nursery. As he pulled up at the end of a pass, he crossed over an area of trees and heard a “loud bang.” He attempted to maneuver the airplane to land in an open field; however, the airplane “ran out of altitude and airspeed” and impacted the ground. Examination of the airplane revealed that during the impact sequence the engine and upper wing were separated from their respective mounting locations. Postaccident examination of the engine revealed that when rotating the propeller, the drivetrain would rotate freely, and no binding was noted. All the engine cylinders were intact. The supercharger impeller was intact, but further examination revealed that it was not rotating when the propeller was moved by hand. The rear accessory/diffuser housing was removed to expose the supercharger impeller and no damage was noted on the external impeller blades; however, the rear splined impeller shaft ball bearing spacer (P/N 13814) and supercharger impeller (P/N 12788) splines were found to have sheared, allowing the impeller to freewheel. Review of the airplane’s maintenance logs revealed that the engine had accumulated 7,598 total hours of operation and 1,031 hours since its most recent overhaul. ## Aircraft - Registration: [N8923H](https://openairdocs.org/aircraft/N8923H), registered now, S/N 1567, built 1975 (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: 1567 - Year built: 1975 - Airframe hours: 5600 - Engines: Pratt & Whitney R-1340-AN-1 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Salem Spray Service Inc - Registered owner: Salem Spray Service Inc - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, April 12, 2022 - Departed: 9NJ6, Fairton, NJ - Equipment: Stall warning system, ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 61; injuries: serious; flight instructor, commercial; airplane ratings: single-engine land, single-engine sea; instrument ratings: airplane; medical: class 2, with waivers/limitations; last flight review April 10, 2021; seat: single; restraint: 3-point; flight hours: 6,054 total, 3,480 in this make and model, 5,830 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: 230° at 8 knots, gusting 16 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 70 °F - Altimeter: 29.95 inHg - Observed at: KMIV, 11 nm away - METAR: METAR KMIV 021354Z AUTO 23008G16KT 10SM CLR 28/21 A2995 RMK AO2 SLP140 T02780211= ## 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 20220702007149A](https://openairdocs.org/incident/20220702007149A), Jul 2, 2022: Grumman Acft Eng Cor-Schweizer G-164A, Hopewell, NJ, Substantial damage. While performing a turn around on an active agricultural spray run the aircraft supercharger failed (impeller splines) resulting in an immediate loss of thrust… ## Docket (4 files) The files NTSB released with the investigation on July 24, 2024, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=105421. 13.5 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 11.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17203540&FileExtension=pdf&FileName=NTSB%20Form%206120%20-%20completed%20_Redacted-Rel.pdf - Weather reports and records (item 2, PDF, 2 pages, 130 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17203981&FileExtension=pdf&FileName=MOR%20Weather%20at%20KMIV-Rel.pdf - Investigative photographs (item 3, PDF, 4 pages, 1.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17204406&FileExtension=pdf&FileName=Investigative%20Photo%20Array-Rel.pdf - Memorandum for record - engine examination (item 4, PDF, 2 pages, 92 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17353723&FileExtension=pdf&FileName=MOR-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.