Bell UH-1B accident near Walla Walla, Washington, April 22, 1995
On April 22, 1995 at about 4:50 pm local time, a Bell UH-1B (helicopter), registered N39SD, was substantially damaged in an accident near Walla Walla, Washington. It was an other work-use flight under external-load helicopter rules (Part 133). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
TOTAL FAILURE OF THE FREEWHEELING SPRAG UNIT. A FACTOR TO THE ACCIDENT WAS: SUITABLE TERRAIN WAS NOT AVAILABLE FOR LANDING.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 22, 1995 · about 4:50 pm local time
- Place
- Walla Walla, Washington · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell UH-1B · all UH-1Bs on the register
- Registration
- N39SD · registry record · serial 63-8699
- 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 STATED THAT DURING AN EXTERNAL LOAD OPERATION, JUST AFTER THE LOAD CLEARED THE GROUND THE HELICOPTER SHUTTERED AND MADE A LOUD SCRAPING NOISE FOLLOWED BY LOW ROTOR RPM. THE PILOT RELEASED THE LOAD AND MANEUVERED FOR AN EMERGENCY LANDING. DURING THE MANEUVER, THE HELICOPTER COLLIDED WITH TREES. DURING THE POST CRASH INSPECTION, IT WAS FOUND THAT THE FREEWHEELING ONE-WAY CLUTCH ASSEMBLY HAD FAILED IN FLIGHT. THE CLUTCH ASSEMBLY APPEARED TO BE WORN AND THE INNER CLUTCH RACE DISPLAYED SIGNS OF BRINELLING.
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; rotorcraft: helicopter
- Flight time: 20,733 hours in all; 2,297 in this make and model
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 4,810 hours
- Last inspection: annual inspection, April 8, 1995; 34 hours since
- Maximum gross weight: 8,500 lb
- Seats: 6
- Landing gear: fixed
- Engine: Lycoming T53-L13B-22 (turboshaft); 0 hours total
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 30 statute miles
- Sky: clear
- Temperature: 50°F (10°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.