# NTSB ANC12CA059: Dosser Dale A Blade 582, N907AD, Two Rivers, AK, June 20, 2012 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: June 20, 2012, 01:30 local (09:30 UTC) - Place: Two Rivers, AK - Coordinates: 65.059722, -146.316665 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=65.0597&lon=-146.3167&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report October 15, 2012 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Federal Aviation Administration - NTSB case key (mKey): 84116 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC12CA059 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/84116/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=84116 - Page: https://openairdocs.org/ntsb/ANC12CA059 ## Probable cause The total loss of engine power during cruise flight due to fouled spark plugs, which resulted from a stuck mixture control. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine fuel and control: fuel control/carburetor](https://openairdocs.org/ntsb-findings/01057322): Aircraft › Aircraft power plant · Malfunction (probable cause); cases with it: [Dosser Dale A BLADE 582, 1 case](https://openairdocs.org/ntsb-findings/01057322/cases.md?model=05901OU), [All aircraft, 195 cases](https://openairdocs.org/ntsb-findings/01057322/cases.md) - [Terrain: rough terrain](https://openairdocs.org/ntsb-findings/03021015): Environmental issues › Physical environment · Effect on equipment; cases with it: [Dosser Dale A BLADE 582, 1 case](https://openairdocs.org/ntsb-findings/03021015/cases.md?model=05901OU), [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: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Dosser Dale A BLADE 582, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=05901OU), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Landing: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Dosser Dale A BLADE 582, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=05901OU), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis The pilot reported that the airplane was in level cruise flight when the engine began to run rough and lose power, followed by a complete loss of engine power. He made a forced landing on a mountain ridge. During the forced landing, the nose wheel encountered rough terrain and collapsed rearward, which resulted in substantial damage to the fuselage. Postaccident examination revealed that the engine’s mixture control malfunctioned, which resulted in fouled spark plugs. ## Factual narrative The pilot reported that while in level cruise flight the engine began to run rough and lose power, followed by a complete loss of engine power. He made a forced landing to a trail on a mountain ridge. During the forced landing, the nose wheel encountered rough terrain and collapsed rearward. The airplane sustained substantial damage to the fuselage. A postaccident examination by the pilot, revealed the mixture control stuck in the full rich position, which fouled the spark plugs. ## Aircraft - Registration: [N907AD](https://openairdocs.org/deregistered/N907AD-2018-01-10), registration cancelled 2018-01-10, S/N 1151-0398-7W954, built 1998 (OpenAirDocs) - Reported make and model: DOSSER DALE A BLADE 582 - Registry model: [Dosser Dale A BLADE 582](https://openairdocs.org/model/dosser-dale-a-blade-582) (registry code 05901OU) (OpenAirDocs) - Registry engine: [Rotax 582DCDI](https://openairdocs.org/engine/rotax-582dcdi) (registry code 55562, 2 cycle) (OpenAirDocs) - Category: Weight-shift, amateur-built - Serial number: 1151-0398-7W954 - Engines: ROTAX 582DCDI 65 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental light sport (Special) - Departed: 95Z, North Pole, AK - Destination: 95Z, North Pole, AK - Flight plan: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 24; injuries: none; sport pilot; medical: sport pilot; seat: front; flight hours: 73 total, 73 in this make and model ## Weather - Conditions: Visual (VMC), Dusk - Wind: calm - Visibility: 10 statute miles ## Docket (1 files) The files NTSB released with the investigation on August 8, 2012, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=84116. 731 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 731 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40374575&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.