# NTSB LAX91LA214: Grumman G164B, N48658, Yuba City, CA, May 14, 1991

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: May 14, 1991, 16:10 local (23:10 UTC)
- Place: Yuba City, CA
- Coordinates: 39.050506, -121.610977 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=39.0505&lon=-121.6110&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report May 27, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27207
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA214
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27207/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA214

## Probable cause

FATIGUE IN THE PROPELLER BLADE WHICH LED TO ITS ULTIMATE FAILURE.  FACTORS RELATING TO THIS ACCIDENT WERE THE SOFT TERRAIN CONDITIONS ON WHICH THE AIRPLANE LANDED AND A BERM ACROSS THE AIRPLANE'S GROUND PATH.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Airframe/component/system failure/malfunction, maneuvering - aerial application
  - propeller system/accessories,blade - fatigue (cause)
  - propeller system/accessories,blade - separation
- Forced landing, descent - emergency
- Nose over, landing - roll
  - terrain condition - soft (contributing factor)
  - terrain condition - berm (contributing factor)

## Analysis

THE PILOT WAS CONDUCTING AN AERIAL APPLICATION FLIGHT. AS THE AIRPLANE NEARED THE COMPLETION OF A PROCEDURE TURNAROUND THE AIRPLANE BEGAN TO SHAKE VIOLENTLY. THE PILOT REDUCED ENGINE POWER AND LANDED IN A RICE FIELD. DURING THE LANDING ROLL THE PILOT OBSERVED A BERM AND APPLIED FULL BRAKING AND THE AIRPLANE NOSED OVER ONTO ITS BACK. EXAMINATION OF THE PROPELLER DISCLOSED THAT A 6 INCH SECTION OF THE TIP END OF ONE BLADE SEPARATED. THE FRACTURED AREA DISPLAYED FATIGUE STRIATION SIGNATURES.

## Aircraft

- Registration: [N48658](https://openairdocs.org/deregistered/N48658-2022-03-21), registration cancelled 2022-03-21, S/N 125B, built 1976 (OpenAirDocs)
- Reported make and model: GRUMMAN G164B
- 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: 1258
- Airframe hours: 7617
- Engines: P&W R1340AN1 525 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Wagner Aviation
- Registered owner: Wagner Aviation
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: 100 hour, May 6, 1991, 80 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 55; commercial; airplane ratings: single-engine land, multi-engine land; medical: class 2, valid medical--w/ waivers/lim; seat: center; flight hours: 25,000 total, 4,000 in this make and model, 25,000 as pilot in command, 600 in the last 90 days, 250 in the last 30 days, 8 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 340° at 10 knots
- Visibility: 95 statute miles
- Lowest ceiling: none
- Temperature: 75 °F, dew point 48 °F
- Altimeter: 29.00 inHg
- Observed at: MYV, 4 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 19910514015719A](https://openairdocs.org/incident/19910514015719A), May 14, 1991: Scwzer G164B, Yuba City, CA, Substantial damage. Six inches of propeller blade separated due to fatigue. Nosed over on forced landing.

## Other investigations on N48658 (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 LAX92LA259](https://openairdocs.org/ntsb/LAX92LA259), Jun 23, 1992: Grumman G-164B (N48658), Robbins, CA, substantial damage. Probable cause: THE FAILURE OF THE PILOT TO MAINTAIN AN ADEQUATE WING TIP CLEARANCE BETWEEN THE AIRCRAFT AND A DIRT BANK PARALLELING THE AIRSTRIP.

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.

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