# NTSB LAX91LA109: Rockwell S2R-600, N4930X, Corcoran, CA, February 18, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: February 18, 1991, 14:15 local (22:15 UTC)
- Place: Corcoran, CA
- Coordinates: 36.069488, -119.530899 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=36.0695&lon=-119.5309&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report March 31, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27119
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA109
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27119/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA109

## Probable cause

FAILURE OF THE AIRCRAFT ENGINE'S FUEL PUMP VALVE ASSEMBLY BYPASS.

## Sequence of events

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

- Loss of engine power(total) - mech failure/malf, takeoff - initial climb
  - fuel system,pump - failure,total (cause)
  - fluid,fuel - starvation
- Forced landing, descent - emergency
- Nose over, landing - flare/touchdown
  - terrain condition - soft (contributing factor)

## Analysis

THE AIRCRAFT EXPERIENCED A TOTAL LOSS OF POWER ABOUT 50 FEET ABOVE THE GROUND DURING TAKEOFF INITIAL CLIMB. THE PILOT ATTEMPTED A FORCED LANDING STRAIGHT AHEAD TO AN OPEN FIELD. AT TOUCHDOWN, THE AIRCRAFT'S LANDING GEAR SUNK INTO THE SOFT, WET SOIL CAUSING THE AIRCRAFT TO NOSE OVER. AN EXAMINATION OF THE ENGINE AND ENGINE ACCESSORIES DETERMINED THAT THE ENGINE'S FUEL PUMP VALVE ASSEMBLY BYPASS HAD FAILED. THE FAILURE CAUSED FUEL STARVATION RESULTING IN A TOTAL LOSS OF ENGINE POWER.

## Aircraft

- Registration: [N4930X](https://openairdocs.org/deregistered/N4930X-2012-12-18), registration cancelled 2012-12-18, S/N 2132R, built 1974 (OpenAirDocs)
- Reported make and model: Rockwell S2R-600
- Registry model: [Rockwell International S-2R](https://openairdocs.org/model/rockwell-international-s-2r) (registry code 7630202) (OpenAirDocs)
- Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 2132R
- Engines: P&W R-1340 600 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Salyer Farms Airport
- Registered owner: Salyer Farms Airport
- Last inspection: Unknown, January 2, 2000

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 47; commercial, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; flight hours: 20,000 total, 1 in this make and model, 20,000 as pilot in command, 220 in the last 90 days, 50 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 135° at 3 knots
- Visibility: 10 statute miles
- Lowest ceiling: none

## 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 19910218002789A](https://openairdocs.org/incident/19910218002789A), Feb 18, 1991: Ayres S2RR1340REST, Corcoran, CA, Substantial damage. Engine quit on initial climb. Nosed over landing in soft soil. Engine fuel pump valve assembly by pass had failed.

## Other investigations on N4930X (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 LAX93LA303](https://openairdocs.org/ntsb/LAX93LA303), Jul 28, 1993: Ayres S2R (N4930X), Stratford, CA, destroyed. Probable cause: THAT THE PILOT MISJUDGED THE AIRPLANE'S ALTITUDE. FACTORS RELATING TO THIS ACCIDENT WERE THE PILOT'S FATIGUE AND THE LIGHT CONDITIONS.

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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