# NTSB LAX91LA140: Sikorsky S-58J, N27AR, Chowchilla, CA, March 22, 1991

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: March 22, 1991, 11:00 local (19:00 UTC)
- Place: Chowchilla, CA
- Coordinates: 37.069171, -120.270317 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.0692&lon=-120.2703&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report January 25, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 27143
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX91LA140
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/27143/pdf
- Page: https://openairdocs.org/ntsb/LAX91LA140

## Probable cause

1) THE PILOT NOT FOLLOWING THE PERFORMANCE DATA FOR THE AIRCRAFT, AND 2) THE PILOT'S INFLIGHT DECISION TO TURN THE AIRCRAFT, WHICH WAS AT OR NEAR MAXIMUM GROSS WEIGHT, IN SUCH A DIRECTION THAT REQUIRED MORE POWER THAN WAS AVAILABLE FOR THE GIVEN FLIGHT CONDITION.  A FACTOR IN THIS ACCIDENT WAS THE PILOT'S INABILITY TO TAKE REMEDIAL ACTION DUE TO THE LOW ALTITUDE OF THE AIRCRAFT.

## Sequence of events

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

- Loss of control - in flight, maneuvering - aerial application
  - performance data - inaccurate, pilot in command (cause)
  - in-flight planning/decision - improper, pilot in command (cause)
  - altitude - inadequate (contributing factor)
  - remedial action - not possible, pilot in command (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled
  - terrain condition - ground

## Analysis

THE AIRCRAFT HAD JUST COMPLETED A CHEMICAL APPLICATION RUN OF APPROXIMATELY 1/2 MILE IN LENGTH FROM NORTH TO SOUTH. THE PILOT ATTEMPTED TO TURN THE HELICOPTER FROM A HEADING OF SOUTH, THROUGH A HEADING OF EAST, TO THE NORTH OR WEST. DURING THE TURN, THE AIRCRAFT DESCENDED IN UNCONTROLLED FLIGHT UNTIL IT COLLIDED WITH THE TERRAIN.  THE AIRCRAFT HAD BEEN REFUELED AND LOADED WITH ABOUT 350 GALLONS OF CHEMICALS ABOUT 5 MINUTES BEFORE THE ACCIDENT.  NO MECHANICAL DEFICIENCIES COULD BE FOUND. THE WIND AT THE ACCIDENT SITE WAS REPORTED FROM THE SOUTH.  DURING THE TURN FROM THE SOUTH TO THE NORTH, THE AIRCRAFT PASSED THROUGH A HEADING WHERE THE WIND WOULD BE OFF THE RIGHT REAR OF THE AIRCRAFT.  AT THIS PARTICULAR HEADING, MAXIMUM POWER WOULD BE REQUIRED TO SUSTAIN FLIGHT.  IN CONSIDERATION OF THE AIRCRAFT'S WEIGHT; DIRECTION OF TURN; WIND DIRECTION; AND WITNESS REPORTS, THE AIRCRAFT EXPERIENCED SETTLING WITH POWER.  DURING THE HOVER MANEUVER, THE AIRCRAFT WAS AT A RELATIVELY LOW ALTITUDE WHICH PROHIBITED RECOVERY.

## Aircraft

- Registration: [N27AR](https://openairdocs.org/deregistered/N27AR-2012-08-23), registration cancelled 2012-08-23, S/N 56-4327, built 1957 (OpenAirDocs)
- Reported make and model: SIKORSKY S-58J
- Registry model: [Sikorsky S-58J](https://openairdocs.org/model/sikorsky-s-58j) (registry code 8141814) (OpenAirDocs)
- Registry engine: [Wright R-1820 series](https://openairdocs.org/engine/wright-r-1820-series) (registry code 67020, reciprocating) (OpenAirDocs)
- Category: Helicopter
- Serial number: 58-735
- Engines: WRIGHT 989C9HE-2 1425 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: Federico Helicopters Inc.
- Last inspection: Unknown, January 2, 2000

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 44; commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane, helicopter; medical: class 2, valid medical--no waivers/lim.; flight hours: 6,940 total, 247 in this make and model, 6,540 as pilot in command

## Weather

- Conditions: Visual (VMC), Day
- Wind: 180° at 8 knots
- Visibility: 20 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 19910322007269A](https://openairdocs.org/incident/19910322007269A), Mar 22, 1991: Skrsky S58J, Chowchilla, CA, Substantial damage. Helicopter descended to ground impact and broke up during a hover turn around from a spray run.

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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