# NTSB LAX87LA105: Sikorsky S-58B, N5594C, Los Angeles, CA, January 31, 1987

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: January 31, 1987, 07:39 local (15:39 UTC)
- Place: Los Angeles, CA
- Coordinates: 34.020618, -118.279685 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=34.0206&lon=-118.2797&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor, 1 uninjured
- Status: Completed, report July 5, 1988
- Report: Approved by Office Director
- NTSB case key (mKey): 25513
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX87LA105
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/25513/pdf
- Page: https://openairdocs.org/ntsb/LAX87LA105

## Sequence of events

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

- In flight collision with object, maneuvering
  - object - electrical tower(marked) (contributing factor)
  - planned approach - poor, pilot in command (contributing factor)
  - descent - premature, pilot in command (cause)
  - visual lookout - not maintained, pilot in command (cause)
  - diverted attention, pilot in command (cause)
  - crew/group coordination - poor, pilot in command (contributing factor)
- Hard landing, descent - emergency
  - rotor system,main rotor blade - loss,partial
  - proper descent rate - not possible, pilot in command

## Analysis

A SIKORSKY S-58B COLLIDED WITH A MARKED 253 FT AGL ANTENNA TOWER (TWR) WHILE MANEUVERING OVER EXTERNAL LOAD LIFT SITE. THE PLT INDICATED THAT HE WAS SITTING IN THE RIGHT SEAT OF THE ACFT IN A RIGHT DESCENDING ORBIT CONDUCTING A SITE RECON AND THAT HE WAS AWARE OF THE TWRS PRESENCE. THE PLT STATED THAT HE MISJUDGED HIS POSITION RE THE TWR. THE PLT INDICATED THAT HE STARTED A DESCENT WHILE DISCUSSING THE LIFT PLAN WITH HIS CREWCHIEF. BOTH CREWMEMBERS WHO WERE ON THE RIGHT SIDE OF THE ACFT WERE LOOKING TO THE RIGHT AT THE LIFT SITE WHEN THE HELICOPTER STRUCK THE ANTENNA TWR. THE ANTENNA TWR WAS A PROPERLY MARKED OBSTRUCTION AND MET THE LIGHTING REQUIREMENTS IN ACCORDANCE WITH FAA ADVISORY CIRCULAR 70/7460-1. THE COLLISION DAMAGED THE MAIN ROTOR.

## Aircraft

- Registration: N5594C (not matched to a registry record)
- Reported make and model: SIKORSKY S-58B
- Category: Helicopter
- Serial number: 58-692
- Airframe hours: 7478
- Engines: P&W PT6T3 900 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Other work use, Part 133
- Operator: Aris Helicopter Ltd
- Registered owner: Aris Helicopter Ltd
- Airworthiness certificate: Standard, Normal; Standard, Utility
- Last inspection: Continuous airworthiness, January 30, 1987, 9 hours before
- Departed: HRR, HAWTHORNE, CA
- Destination: HRR, HAWTHORNE, CA
- Flight plan: Company VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 35; commercial, airline transport, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: right; toxicology performed; flight hours: 5,226 total, 700 in this make and model, 5,100 as pilot in command, 35 in the last 90 days, 20 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 40° at 6 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 48 °F, dew point 43 °F
- Altimeter: 30.00 inHg
- Observed at: LAX, 8 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 19870131057199A](https://openairdocs.org/incident/19870131057199A), Jan 31, 1987: Skrsky S58B, Los Angeles, CA, Substantial damage. Struck a radio antenna tower while circling a prospective external load site.

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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