Amateur-built Prospector FK1 accident near Gibbonsville, Idaho, April 17, 2004
On April 17, 2004 at about 6:00 pm local time, a amateur-built Prospector FK1, registered N5XK, was substantially damaged in an accident near Gibbonsville, Idaho. It was a personal flight under general aviation rules (Part 91). 2 people were seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's failure to apply carburetor heat in icing conditions which resulted in a loss of engine power while in cruise flight. Factors contributing to the accident are unsuitable terrain for an emergency landing , trees and mountainous terrain.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 17, 2004 · about 6:00 pm local time
- Place
- Gibbonsville, Idaho · map
- Type
- Accident
- Injuries
- 2 people were seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built Prospector FK1
- Registration
- N5XK · no longer on the register · serial 002
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
In a written statement the pilot reported that approximately 10 miles south of Lost Trail Pass he decided to turn back due to deteriorating weather ahead. The pilot stated that during the turn he lost track of the two other aircraft that made up the flight of three. The pilot stated he was "trying to locate [the] other two A/C [aircraft] to the exclusion of the engine instruments". The pilot stated that as the airplane reached the summit he added power "as I was too low." Concurrent with the increase in power, the engine quit. The pilot maneuvered the airplane in an effort to avoid rising terrain, however, during the maneuver the airplane collided with multiple trees eventually impacting terrain in an inverted position. The pilot rated passenger reported the weather conditions along the route of flight began to deteriorate, and the pilot-in-command of the accident airplane elected to return to Stevensville. The passenger reported that shortly after making the decision to return, the airplane's engine began to lose power. After losing power, the airplane stalled and collided with terrain. The pilot and pilot rated passenger both indicated the loss of power was the result of carburetor ice. The pilot was operating the airplane in moderate snow showers. The pilot's written report indicated the outside air temperature was approximately 35 degrees Fahrenheit.
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: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instructor: airplane single-engine; instrument: airplane
- Flight time: 3,344 hours in all; 618 in this make and model; 29 in the last 90 days; 24 in the last 30 days
- Last flight review: September 14, 2003
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: serious injuries
The aircraft
- Airframe total time: 618 hours
- Last inspection: annual inspection, October 30, 2003; 34 hours since
- Maximum gross weight: 2,100 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming O-320-E2D (piston); 0 hours total
The flight
- Departed from: 32S Stevensville MT at 4:30 pm
- Destination: 06U Jackpot NV
- Flight plan: not recorded
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: not recorded; not recorded
- Temperature: 36°F (2°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 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.