North American OV-10A accident near Porterville, California, September 6, 2006
On September 6, 2006 at about 5:39 pm local time, a North American OV-10A, registered N419DF, was destroyed in an accident near Porterville, California. It was a public-use flight (state) under public-use (government) rules. 2 people were killed. The weather was visual conditions (good weather).
Preview. This page is not yet listed for search engines.
The NTSB's probable cause their words, unchanged
the pilot's failure to maintain adequate terrain clearance while maneuvering over rising terrain in a box canyon. Also causal was the pilot's failure to adhere to procedures/directives regarding minimum altitude requirements.
Source: NTSB aviation accident database, copy made October 4, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 6, 2006 · about 5:39 pm local time
- Place
- Porterville, California · map
- Type
- Accident
- Injuries
- 2 people were killed.
- Weather
- visual conditions (good weather)
- Aircraft
- North American OV-10A · all OV-10As on the register
- Registration
- N419DF · registry record · serial 305104M56
- Damage
- Destroyed
- Flight
- Public-use flight (state) · public-use (government) rules
The NTSB's narrative final · quoted from the NTSB record
The airplane impacted rising mountainous terrain in a box-like canyon while performing mission-related low altitude aerial surveillance. The pilot was under contract to fly California Department of Forestry (CDF) personnel over an area where three fires had occurred and to search for newly developing fires. During the 14-minute-long flight, the pilot proceeded to the designated area and commenced providing his observer-crewmember with a viewing opportunity. The pilot flew up and down the canyon's drainage area, which was surrounded by higher elevation terrain. Witnesses initially observed the airplane flying 1,000 to 1,500 feet above ground level (agl). Subsequently, the airplane was observed flying 100 to 150 feet agl. Seconds before the crash, a witness located 3/4-mile downslope from the accident site observed the airplane proceeding over progressively higher elevation terrain while flying between 400 to 600 feet agl, and with its nose pitched upward at a 40-degree angle. Another witness about 1/2-mile downslope from the accident site reported hearing airplane engine noise consistent with high rpm, the sound of a crash, and the sound of a falling tree followed by an explosion. The airplane impacted 125-foot-tall trees on 25- to 40-degree upsloping terrain, fragmented, and was destroyed by the post impact fire. Wreckage from the airframe and all six propeller blades were examined on the 6,240-foot mean sea level mountainside. The turboprop engines were subsequently recovered and torn down. A plethora of evidence was found consistent with rotational operation at high power followed by sudden stoppage. No evidence of any preimpact airframe or engine malfunction was observed. CDF had published a restriction specifying that the accident airplane not be flown lower than 500 feet agl during missions. The restriction document was found in the airplane wreckage. Additionally, CDF had not authorized the pilot to fly missions at any time below 500 feet agl.
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: airline transport pilot, flight instructor
- Ratings: multi-engine land; single-engine land; instructor: airplane single-engine; instrument: airplane
- Flight time: 12,516 hours in all; 860 in this make and model; 127 in the last 90 days; 27 in the last 30 days; 12,254 as pilot in command
- Last flight review: May 1, 2006
- Medical certificate: Class 1 (with waivers/limitations)
- Seat: frt
- Injury: fatal
The aircraft
- Airframe total time: 7,439 hours
- Last inspection: 100-hour inspection, August 1, 2006; 23 hours since
- Maximum gross weight: 10,500 lb
- Seats: 2
- Landing gear: retractable
- Engine: Garrett-Airesearch T76-G-419 (turboprop); 0 hours total
- Fire on the ground
- Operator: California Dept. Of Forestry & Fire Protection
The flight
- Departed from: PTV Porterville CA at 5:25 pm
- Destination: PTV Porterville CA
Weather at the time
- Light: daylight
- Wind: from 290° at 4 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 88°F (31°C), dew point 61°F (16°C)
- Altimeter: 29.97 inHg
- Observation at 5:35 pm from PTV, 22 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The docket at the NTSB holds the report as a PDF and the investigation's photographs and documents. This site never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number LAX06GA287.