# NTSB FTW91LA105: Sikorsky 58H, N4582B, Corsicana, TX, June 20, 1991

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: June 20, 1991, 16:30 local (21:30 UTC)
- Place: Corsicana, TX
- Coordinates: 32.079429, -96.460571 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=32.0794&lon=-96.4606&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 6 uninjured
- Status: Completed, report March 31, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 23351
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW91LA105
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/23351/pdf
- Page: https://openairdocs.org/ntsb/FTW91LA105

## Probable cause

FAILURE OF THE MAGNETO. FACTORS WERE THE HELICOPTER'S POSITION OVER WATER, THE TAILWIND, AND THE INADEQUATE MAIN ROTOR RPM PRIOR TO TOUCHDOWN.

## 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, cruise
  - ignition system,magneto - failure,total (cause)
- Forced landing, maneuvering - turn to landing area (emergency)
  - terrain condition - water (contributing factor)
  - autorotation - performed, pilot in command
  - weather condition - tailwind (contributing factor)
- Hard landing, landing - flare/touchdown
  - adequate rotor rpm - not possible, pilot in command (contributing factor)
  - landing gear,main gear strut - overload

## Analysis

THE HELICOPTER WAS IN CRUISE FLIGHT OVER A LAKE WHEN AN ENGINE POWER LOSS OCCURRED. THE PILOT ENTERED AUTOROTATION AND MANEUVERED DOWNWIND TOWARD THE SHORE LINE.  THE HELICOPTER LANDED HARD AND THE RIGHT MAIN GEAR STRUT COLLAPSED, PENETRATING THE FUSELAGE. ENGINE EXAMINATION SHOWED A TOTAL FAILURE OF THE MAGNETO. IT HAD RECENTLY UNDERGONE REPAIR AND INSPECTION AT AN ENGINE SHOP.

## Aircraft

- Registration: N4582B (not matched to a registry record)
- Reported make and model: SIKORSKY 58H
- Category: Helicopter
- Serial number: 14-8079
- Engines: WRIGHT R-1820-84C 1525 horsepower reciprocating
- Damage: Substantial damage
- Flight: Business, Part 91
- Operator: Bradford S. Ladue
- Registered owner: Bradford S. Ladue
- Last inspection: 100 hour, January 2, 2000
- Departed: HQZ, MESQUITE, TX
- Destination: SPX, HOUSTON, TX

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 39; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; flight hours: 16,112 total, 3,360 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 210° at 11 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 90 °F, dew point -0 °F
- Altimeter: 29.00 inHg

## 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 19910620022839A](https://openairdocs.org/incident/19910620022839A), Jun 20, 1991: Skrsky S58H, Corsicana, TX, Substantial damage. Engine failed over chambers lake. Stretched autorotation to land on shore. Impact put strut thru cabin,bad magneto.

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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