Hawkins & Powers UH-1B accident near North Bend, Washington, November 12, 1993
On November 12, 1993 at about 7:30 pm local time, a Hawkins & Powers UH-1B (helicopter), registered N91NW, was substantially damaged in an accident near North Bend, Washington. It was an other work-use flight under external-load helicopter rules (Part 133). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
TOTAL FAILURE OF THE INTERMEDIATE GEARBOX. THE LACK OF SUITABLE TERRAIN FOR AN AUTOROTATION WAS A FACTOR.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 12, 1993 · about 7:30 pm local time
- Place
- North Bend, Washington · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Hawkins & Powers UH-1B
- Registration
- N91NW · no longer on the register · serial 62-1915
- Damage
- Substantial damage
- Flight
- Other work-use flight · external-load helicopter rules (Part 133)
The NTSB's narrative final · quoted from the NTSB record
THE PILOT HEARD LOUD GRINDING SOUNDS FROM THE REAR OF THE AIRCRAFT, FOLLOWED BY BANGING SOUNDS AND A LOSS OF DIRECTIONAL CONTROL. HE JETTISONED HIS LOGS, THEN HIS LONG LINE, AND EXECUTED A POWERED AUTOROTATION INTO THE TREES, SUBSTANTIALLY DAMAGING THE AIRCRAFT. THE 42 DEGREE INTERMEDIATE GEARBOX WAS EXAMINED AND MULTIPLE ORIGIN FATIGUE CRACKS WERE FOUND IN FRAGMENTS OF THE INPUT PINION GEAR.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land; instrument: helicopter; rotorcraft: helicopter
- Flight time: 11,800 hours in all; 1,500 in this make and model
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 10,106 hours
- Last inspection: 100-hour inspection, November 8, 1993; 25 hours since
- Maximum gross weight: 8,500 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming T53-L11D (turboshaft); 0 hours total
- Operator: Northwest Helicopters, INC.
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 2 statute miles
- Sky: clear
- Temperature: 61°F (16°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.