North American OV-10A N419DF

Summary

On 6 September 2006 at about 17:39 local time, a North American OV-10A registered N419DF, operated by California Dept. of Forestry & Fire Protection, was involved in an accident near Porterville, California, United States. 2 people were on board and 2 died. The aircraft was destroyed. The NTSB has published a probable cause for this accident; it is quoted in full below.

Date

6 September 2006 at 17:39

Classification

Accident

Location

Porterville, California, United States

Coordinates

36.2317, -118.6850

Aircraft

North American OV-10A

Registration

N419DF

Category

Airplane

Engines

2

Operator

California Dept. of Forestry & Fire Protection

Operating rule

Public Use

Phase of flight

Not recorded

Route

Porterville → Porterville

Aircraft damage

Destroyed

Weather

VMC

Light

Day

NTSB number

LAX06GA287

2 people died.

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.

Quoted verbatim from the NTSB record. This site does not paraphrase or interpret it.

Read the full NTSB narrative

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.

Quoted verbatim from the NTSB record.