# NTSB SEA89LA170: Hughes 369D, N1088N, Petersburg, AK, September 9, 1989

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: September 8, 1989, 18:30 local (Sep 9, 1989, 01:30 UTC)
- Place: Petersburg, AK
- Coordinates: 57.050022, -132.620132 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=57.0500&lon=-132.6201&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 5 uninjured
- Status: Completed, report June 26, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 41078
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA89LA170
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41078/pdf
- Page: https://openairdocs.org/ntsb/SEA89LA170

## Probable cause

THE PILOT FAILED TO OBTAIN CLEARANCE OVER TREES. CONTRIBUTING TO THE ACCIDENT WAS: THE AIRCRAFT BEING ABOVE ITS MAXIMUM CERTIFICATED GROSS WEIGHT LIMITATION AND THE TREES.

## Sequence of events

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

- In flight collision with object, takeoff - initial climb
  - aircraft weight and balance - exceeded, pilot in command (contributing factor)
  - object - tree(s) (contributing factor)
  - clearance - not attained, pilot in command (cause)

## Analysis

AFTER PICKING UP PASSENGERS WITH EQUIPMENT, THE PILOT ATTEMPTED TWICE TO LIFT OFF, BUT WAS UNSUCCESSFUL. ON THE THIRD ATTEMPT, THE HELICOPTER ATTAINED AN ALTITUDE OF APRX 20 FT; HOWEVER, IT DID NOT CLEAR A LINE OF TREES LOCATED 50 FT FROM THE LIFT-OFF POINT AND 30 FEET IN HEIGHT. AFTER THE ACCIDENT, THE PASSENGERS AND EQUIPMENT WERE WEIGHED. THE HELICOPTER WAS FOUND TO HAVE BEEN OPERATING 200 POUNDS OVER ITS MAX GROSS WEIGHT LIMITATION. THERE WERE NO REPORTED MECHANICAL FAILURES OR MALFUNCTIONS.

## Aircraft

- Registration: [N1088N](https://openairdocs.org/aircraft/N1088N), registered now, S/N 300679D, built 1980 (OpenAirDocs)
- Reported make and model: HUGHES 369D
- Registry model: [Hughes Helicopters HUGHES 369D](https://openairdocs.org/model/hughes-helicopters-hughes-369d) (registry code 4470706) (OpenAirDocs)
- Registry engine: [Allison 250 SER 250HP](https://openairdocs.org/engine/allison-250-ser-250hp) (registry code 03002, turbo-shaft) (OpenAirDocs)
- Category: Helicopter
- Serial number: 300679D
- Engines: ALLISON 250-C20B 420 horsepower turbo shaft
- Damage: Substantial damage
- Flight: Part 135
- Operator: Temsco Helicopters Inc.
- Registered owner: Unknown
- Flight plan: Company VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 50; commercial; airplane ratings: single-engine land; medical: class 2, valid medical--w/ waivers/lim; flight hours: 7,700 total, 5,000 in this make and model, 7,300 as pilot in command, 257 in the last 90 days, 110 in the last 30 days, 6 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 270° at 10 knots
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: 79 °F

## 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 19890908034079A](https://openairdocs.org/incident/19890908034079A), Sep 8, 1989: Hughes 369D, Petersburg, AK, Substantial damage. Tried to depart small clearing on a island,200 lbs over gross. Unable to climb, struck 30 foot high 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.

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