# NTSB WPR09CA415: Paul B. Johnson Avid Mark IV, N333PD, Nampa, ID, August 21, 2009 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: August 21, 2009, 09:30 local (15:30 UTC) - Place: Nampa, ID - Coordinates: 43.523056, -116.6875 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.5231&lon=-116.6875&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 15, 2009 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 74591 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR09CA415 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/74591/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=74591 - Page: https://openairdocs.org/ntsb/WPR09CA415 ## Probable cause The airplane's encounter with tall vegetation that ensnared the landing gear during an off-field precautionary landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Power plant: engine cowling system](https://openairdocs.org/ntsb-findings/01057110): Aircraft › Aircraft power plant · Malfunction (probable cause); cases with it: [Johnson Paul B AVID MARK IV, 1 case](https://openairdocs.org/ntsb-findings/01057110/cases.md?model=05604RH), [All aircraft, 11 cases](https://openairdocs.org/ntsb-findings/01057110/cases.md) - [Terrain: rough terrain](https://openairdocs.org/ntsb-findings/03021015): Environmental issues › Physical environment · Effect on equipment (probable cause); cases with it: [Johnson Paul B AVID MARK IV, 1 case](https://openairdocs.org/ntsb-findings/03021015/cases.md?model=05604RH), [All aircraft, 442 cases](https://openairdocs.org/ntsb-findings/03021015/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) (defining event); cases with it: [Johnson Paul B AVID MARK IV, 1 case](https://openairdocs.org/ntsb-events/340/sequence.md?model=05604RH), [All aircraft, 820 cases](https://openairdocs.org/ntsb-events/340/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Johnson Paul B AVID MARK IV, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=05604RH), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Johnson Paul B AVID MARK IV, 1 case](https://openairdocs.org/ntsb-events/096/sequence.md?model=05604RH), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis 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. ## Factual narrative The pilot reported that prior to departing on the test flight he checked all of the rigging, and 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. The pilot stated that it was at about this time that 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 grabbed 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 post crash 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. ## Aircraft - Registration: [N333PD](https://openairdocs.org/aircraft/N333PD), registered now, S/N 1256D, built 2009 (OpenAirDocs) - Reported make and model: Paul B. Johnson Avid Mark IV - Registry model: [Johnson Paul B AVID MARK IV](https://openairdocs.org/model/johnson-paul-b-avid-mark-iv) (registry code 05604RH) (OpenAirDocs) - Registry engine: [Subaru ALL MDLS A/B](https://openairdocs.org/engine/subaru-all-mdls-a-b) (registry code 59050, 4 cycle) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 1256D - Airframe hours: 24.5 - Engines: Subaru EA-81 108 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Paul B. Johnson - Registered owner: Paul B. Johnson - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, July 12, 2009, 24.5 hours before - Departed: S67, Nampa, ID - Destination: S67, Nampa, ID ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 46; injuries: none; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review July 20, 2009; seat: left; flight hours: 233 total, 13 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 63 °F - Observed at: EUL, 7 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 20090821013289A](https://openairdocs.org/incident/20090821013289A), Aug 21, 2009: Amtr AVIDMARKIV, Nampa, ID, Substantial damage. (-23) Pilot was on a phase one flight in this experimental. After about 20 minutes into an uneventful flight, aircraft had a partial power loss due to rising… ## Docket (1 files) The files NTSB released with the investigation on September 25, 2009, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=74591. 752 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 752 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40319136&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.