# NTSB SEA88LA129: Aerospatiale SA315B, N3128G, Oakridge, OR, July 13, 1988

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: July 13, 1988, 12:30 local (19:30 UTC)
- Place: Oakridge, OR
- Coordinates: 43.739814, -122.410873 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=43.7398&lon=-122.4109&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious
- Status: Completed, report June 7, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 40846
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA88LA129
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40846/pdf
- Page: https://openairdocs.org/ntsb/SEA88LA129

## Sequence of events

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

- Loss of control - in flight, hover
  - clearance - misjudged, pilot in command (cause)
  - object - tree(s) (contributing factor)
  - external load sling/harness - entangled (cause)
  - load jettison - performed
  - external load equipment - improper use of, pilot in command (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

WHILE SLINGING A LOG THE PILOT ALLOWED THE LOG/SLING LINE TO CONTACT A TREE. THE MOMENTUM OF THE LOG AND HELICOPTER BOWED THE TREE OVER WHEN THE LINE CONTACTED IT. THE PILOT CHOSE TO RELEASE THE LOG FROM THE SLING LINE RATHER THAN DISENGAGE THE ENTIRE LINE AND LOG FROM THE HELICOPTER. ONCE THE LOG SEPARATED, THE LINE CAUGHT IN THE TREE WHICH RETURNED TO AN UPRIGHT ATTITUDE AND PULLED THE LINE TIGHT. THE FORCE APPLIED TO THE HELICOPTER AS THE LINE TIGHTENED, IN TURN ROTATED THE HELICOPTER ABOUT ITS LONGITUDINAL AXIS TO A POINT WHEREBY  THE PILOT LOST CONTROL. SHORTLY THEREAFTER THE HELICOPTER DESCENDED INTO THE TREES AND COLLIDED WITH THE TERRAIN.

## Aircraft

- Registration: [N3128G](https://openairdocs.org/deregistered/N3128G-2018-01-17), registration cancelled 2018-01-17, S/N 2488, built 1976 (OpenAirDocs)
- Reported make and model: AEROSPATIALE SA315B
- Registry model: [Aerospatiale SA315B](https://openairdocs.org/model/aerospatiale-sa315b) (registry code 8680615) (OpenAirDocs)
- Registry engine: [Turbomeca ARTOUSTEIIIB1](https://openairdocs.org/engine/turbomeca-artousteiiib1) (registry code 60066, turbo-shaft) (OpenAirDocs)
- Category: Helicopter
- Serial number: 2488
- Airframe hours: 3184
- Engines: TURBOMECA ARTOUSTE IIIB 562 horsepower turbo shaft
- Damage: Destroyed
- Flight: Other work use, Part 133
- Operator: Gradney Helicopters, Inc.
- Registered owner: Elling Halvorson, Inc.
- Last inspection: 100 hour, June 12, 1988, 46 hours before
- Departed: LOWELL, OR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 38; commercial; airplane ratings: single-engine land, multi-engine land; medical: class 1, valid medical--no waivers/lim.; seat: right; flight hours: 9,915 total, 4,009 in this make and model, 9,765 as pilot in command, 124 in the last 90 days, 51 in the last 30 days, 4 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 140° at 5 knots
- Visibility: 15 statute miles
- Lowest ceiling: 3,500 ft broken
- Temperature: 84 °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 19880713026499A](https://openairdocs.org/incident/19880713026499A), Jul 13, 1988: Aerosp SA315B, Oakridge, OR, Destroyed. Log on sling line caught on a tree,released log but sling line caught in a tree. Pulled helicopter down into trees.

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.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.