Cessna 175C accident near Miles City, Montana, November 5, 2001
On November 5, 2001 at about 1:15 am local time, a Cessna 175C, registered N8347T, was substantially damaged in an accident near Miles City, Montana. It was a personal flight under general aviation rules (Part 91). 1 person was killed. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The separation of the number four cylinder exhaust valve guide from the cylinder head, leading to the failure of the exhaust valve stem and the catastrophic failure of the engine while in cruise flight. Factors include the necessity of attempting a forced landing in rolling/hilly terrain on a very dark night.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 5, 2001 · about 1:15 am local time
- Place
- Miles City, Montana · map
- Type
- Accident
- Injuries
- 1 person was killed.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 175C · all 175Cs on the register
- Registration
- N8347T · no longer on the register · serial 17557047
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During en route cruise, the number four cylinder exhaust valve guide separated from its associated cylinder head. When the aircraft was approximately 12 miles from the airport, the head of the number four cylinder exhaust valve separated from the valve stem. The exhaust valve head then dropped into the number four cylinder where it repeatedly impacted the piston dome and the cylinder head ceiling. This was followed by approximately 30 percent of the piston dome failing inward, resulting in the pressurization of the crankcase through the open exhaust valve port. As a result of the pressurization of the case, one of the number six cylinder pushrod-to-crankcase seals was forced off of its crankcase mounting surface, allowing the majority of the oil to escape from the engine. Soon thereafter, due to thermal stress, the number one connecting rod separated from the crankshaft and punched holes in the crankcase near the number one and number two crankshaft journals. After experiencing a total loss of power, the pilot attempted to land on the uneven rolling terrain, but due to the darkness of the night collided with the terrain.
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
- Flight time: 220 hours in all; 80 in this make and model; 9 in the last 90 days
- Last flight review: September 17, 2000
- Medical certificate: Class 3 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: fatal
The aircraft
- Airframe total time: 2,450 hours
- Last inspection: annual inspection, December 30, 2000; 84 hours since
- Maximum gross weight: 2,450 lb
- Seats: 4
- Landing gear: fixed
- Engine: Continental GO-300-E (piston); 0 hours total
The flight
- Departed from: 9D2 Buffalo SD
- Destination: MLS Miles City MT
- Flight plan: none
Weather at the time
- Light: night, dark
- Wind: from 130° at 6 knots
- Visibility: 20 statute miles
- Sky: clear
- Temperature: 55°F (13°C), dew point 21°F (-6°C)
- Altimeter: 30.03 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.