Cessna 170B accident near Fort Yukon, Alaska, August 31, 1994
On August 31, 1994 at about 8:10 pm local time, a Cessna 170B, registered N4457B, was substantially damaged in an accident near Fort Yukon, Alaska (Upper Coleen River airport). It was a business flight under general aviation rules (Part 91). 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
THE FATIGUE FAILURE OF THE RIGHT MAIN LANDING GEAR SPRING.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 31, 1994 · about 8:10 pm local time
- Place
- Fort Yukon, Alaska · Upper Coleen River · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 170B · all 170Bs on the register
- Registration
- N4457B · registry record · serial 26801
- Damage
- Substantial damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE PILOT LANDED ON THE AIRSTRIP AND DURING THE ROLL OUT THE RIGHT MAIN LANDING GEAR COLLAPSED. EXAMINATION SHOWED A FATIGUED AREA NEAR THE CENTER OF ONE OF THE AXLE'S UPPER MOUNTING BOLT HOLES. THE AIRPLANE HAS BEEN USED ON SKIS DURING THE WINTER MONTHS. THIS FLIGHT WAS ASSOCIATED WITH A HUNT/GUIDE OPERATION. NO PASSENGERS WERE ON BOARD.
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: private
- Ratings: single-engine land; single-engine sea
- Flight time: 4,900 hours in all; 3,000 in this make and model; 100 in the last 90 days; 60 in the last 30 days; 4,840 as pilot in command
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 5,881 hours
- Last inspection: annual inspection, December 21, 1993; 184 hours since
- Maximum gross weight: 2,200 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming O-360-A1A (piston); 0 hours total
The flight
- Departed from: Field Site AK at 2:45 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 30 statute miles
- Sky: clear
- Temperature: 55°F (13°C), dew point 0°F (-18°C)
- Altimeter: 30.00 inHg
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.