Cessna U206G accident near Iliamna, Alaska, June 30, 2010
On June 30, 2010 at about 1:45 am local time, a Cessna U206G, registered N4596U, was substantially damaged in an accident during enroute (cruise) near Iliamna, Alaska. It was flown under charter and air-taxi rules (Part 135). 1 person had minor injuries; 5 others were unhurt. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The total loss of engine power during cruise flight due to a fractured crankshaft.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 30, 2010 · about 1:45 am local time
- Place
- Iliamna, Alaska · map
- Type
- Accident
- Injuries
- 1 person had minor injuries; 5 others were unhurt.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna U206G · all U206Gs on the register
- Registration
- N4596U · registry record · serial U20604990
- Damage
- Substantial damage
- Flight
- Flight · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
The float-equipped airplane was in cruise flight on a sightseeing flight when there was a total loss of engine power. After several unsuccessful attempts to restart the engine, the pilot made a forced landing on tundra-covered terrain, and the airplane nosed over. Postaccident disassembly of the engine found that the crankshaft had fractured at the No. 2 journal. Laboratory examination of the crankshaft found "ladder cracking" associated with the journal fracture, which is consistent with a reduced oil flow and overheating of the surface area. At the time of the accident, the engine had 441 hours of operation since major overhaul, which was performed on October 21, 2008.
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
What happened, in order
- Loss of engine power (total) during enroute (cruise) defining event
- Off-field or emergency landing during emergency descent
- Collision with terrain or object (not controlled flight into terrain) during landing (flare/touchdown)
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip engine power section › Failure
- Environmental issues › Physical environment › Terrain › Rough terrain › Contributed to outcome
Pilot
- Certificate: airline transport pilot, flight instructor
- Ratings: multi-engine land; multi-engine sea; single-engine land; single-engine sea; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 19,900 hours in all; 3,000 in this make and model; 80 in the last 90 days; 80 in the last 30 days
- Last flight review: May 24, 2010
- Medical certificate: Class 1 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 15,612 hours
- Last inspection: 100-hour inspection, June 3, 2010
- Maximum gross weight: 3,800 lb
- Seats: 6
- Landing gear: fixed
- Engine: Cont Motor IO 520 SERIES (piston); 0 hours total
- Operator: Rusts Flying Service INC
The flight
- Departed from: AKN King Salmon AK at 7:45 pm
- Destination: PALH Anchorage AK
Weather at the time
- Light: daylight
- Wind: from 100° at 10 knots
- Visibility: 10 statute miles
- Sky: overcast at 3,300 ft; clear
- Temperature: 54°F (12°C), dew point 45°F (7°C)
- Altimeter: 29.79 inHg
- Observation at 8:53 pm from ILI, 16 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 | 4 |
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.
Other NTSB records under N4596U the same tail number, which may have belonged to a different aircraft at the time
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.