Cessna 170B accident near Santa Rosa, California, January 17, 2004
On January 17, 2004 at about 11:25 pm local time, a Cessna 170B, registered N2502C, was substantially damaged in an accident near Santa Rosa, California. It was a personal 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 failure of the number 2 cylinder barrel due to fatigue. The lack of suitable landing terrain was a factor in the accident.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 17, 2004 · about 11:25 pm local time
- Place
- Santa Rosa, California · 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
- N2502C · no longer on the register · serial 26146
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The engine lost power and the airplane nosed over during a forced landing in a field. Post accident examination revealed that the number 2 cylinder separated from the engine. The engine had accumulated 900 hours since its last major overhaul 13 years prior to the accident; the cylinder had accumulated 1,212 hours since replacement in 1986. The hours on the cylinder prior to that time could not be determined. A metallurgical examination found that the barrel failed due to a fatigue crack. The barrel fractured circumferentially between the 11th and 13th fin from the head. The fracture initiated approximately 1.8 inches below the head and started from the inner diameter below a plated region. The initiation area was a small, flat, thumbnail-shaped region approximately 0.5-inch wide through the wall thickness, with signatures indicative of fatigue. Multiple crack initiation sites were observed in the origin area. From the initiation point, the fracture continued propagating in the circumferential direction with coarse arrest marks over approximately 45 percent of the barrel circumference. No material, manufacture, or plating defects were found. The metallurgical examination could not determine why the cracking occurred at the given location; however, it occurred below the chrome plating. From this, it is possible that the barrel exhausted the available fatigue life at that location, which was lowered by the presence of plating.
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: 171 hours in all; 97 in this make and model; 20 in the last 90 days; 5 in the last 30 days; 108 as pilot in command
- Last flight review: September 4, 2002
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 5,228 hours
- Last inspection: annual inspection, April 22, 2003; 52.6 hours since
- Maximum gross weight: 2,200 lb
- Seats: 2
- Landing gear: fixed
- Engine: Continental C-145-2 (piston); 0 hours total
The flight
- Departed from: STS Santa Rosa CA at 11:05 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 180° at 7 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 55°F (13°C), dew point 45°F (7°C)
- Altimeter: 30.03 inHg
- Observation at 11:53 pm from KSTS, 7 miles away
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.