Amateur-built Avid Mark IV accident near Nampa, Idaho, August 21, 2009
On August 21, 2009 at about 3:30 pm local time, a amateur-built Avid Mark IV, registered N333PD, was substantially damaged in an accident during enroute (cruise) near Nampa, Idaho. 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 airplane's encounter with tall vegetation that ensnared the landing gear during an off-field precautionary landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 21, 2009 · about 3:30 pm local time
- Place
- Nampa, Idaho · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built Avid Mark IV
- Registration
- N333PD · registry record · serial 1256D
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that prior to departing on the test flight he checked all of the rigging, as well as the oil and coolant levels. After performing a takeoff and landing, he stopped and rechecked all fluids. Then he departed to a test area to evaluate slow flight and turn characteristics. The pilot then turned back towards the airport when he observed the coolant temperatures rising, and within a few seconds he could smell coolant. He reduced power, set up an approach to a level field and monitored the temperatures to avoid overheating the engine. The pilot reported that he landed in a bean field, and about 100 feet into the landing roll the bean plants got caught in the landing gear; the airplane subsequently nosed over onto its back. The pilot reported damage to the empennage and fuselage, and that there was no postcrash fire. The pilot further reported that the cause of the engine overheating was the result of a coolant leak from the left intake manifold gasket.
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
- Powerplant sys/comp malf/fail during enroute (cruise) defining event
- Off-field or emergency landing during emergency descent
- Nose over/nose down during landing (landing roll)
The NTSB's findings
- cause Aircraft › Aircraft power plant › Power plant › Engine cowling system › Malfunction
- cause Environmental issues › Physical environment › Terrain › Rough terrain › Effect on equipment
Pilot
- Certificate: private
- Ratings: single-engine land
- Flight time: 233 hours in all; 13 in this make and model
- Last flight review: July 20, 2009
- Medical certificate: Class 3 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 24.5 hours
- Last inspection: condition inspection, July 12, 2009; 24.5 hours since
- Maximum gross weight: 1,250 lb
- Seats: 2
- Landing gear: fixed
- Engine: Subaru EA-81 (piston); 0 hours total
The flight
- Departed from: S67 Nampa ID at 2:30 pm
- Destination: S67 Nampa ID
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 63°F (17°C), dew point 0°F (-18°C)
- Observation at 2:00 pm from EUL, 7 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight 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.