Garlick UH-1H accident near Usk, Washington, September 21, 1999
On September 21, 1999 at about 9:05 pm local time, a Garlick UH-1H (helicopter), registered N32800, was substantially damaged in an accident near Usk, Washington. It was an other work-use flight under external-load helicopter rules (Part 133). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
Fatigue failure of the 90-degree gearbox attachment studs, resulting in separation of the tailrotor and 90-degree gearbox from the vertical fin.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 21, 1999 · about 9:05 pm local time
- Place
- Usk, Washington · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Garlick UH-1H
- Registration
- N32800 · no longer on the register · serial 6616854
- 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 lower surface of the 90-degree gearbox exhibited fracture surfaces of the six attachment studs. Fretting was observed on the lower surface where the gearbox quill assembly was attached. The fracture surfaces for the six attachment studs each showed one or two relatively flat regions with smooth curving boundaries typical of fatigue. Multiple origin sites were identified on each stud, with observed ratchet marks. All of the origin areas were circumferentially aligned with the center of the gearbox, with origins on both sides of each stud, except for one stud, which had an origin area on only one side. In each case, the larger fatigue region had origins on the counter-clockwise side of the stud (as viewed from above, from the center of the gearbox).
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: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 8,300 hours in all; 5,000 in this make and model; 194 in the last 90 days; 51 in the last 30 days; 7,800 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 12,230 hours
- Last inspection: inspection type not recorded, September 9, 1999; 50 hours since
- Maximum gross weight: 9,500 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming T53-13 (turboshaft); 0 hours total
- Fire on the ground
The flight
- Flight plan: not recorded
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 030° at 6 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 82°F (28°C), dew point 39°F (4°C)
- Altimeter: 30.00 inHg
- Observation at 8:56 pm from KGE
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.