# NTSB WPR11LA015: Mischke BD-5B, N525BD, Burlington, WA, October 14, 2010 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Limited investigation · Final report - Date: October 14, 2010, 11:40 local (18:40 UTC) - Place: Burlington, WA - Coordinates: 48.470832, -122.420829 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=48.4708&lon=-122.4208&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed, report June 27, 2011 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 77584 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR11LA015 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/77584/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=77584 - Page: https://openairdocs.org/ntsb/WPR11LA015 ## Probable cause The failure of the sprag clutch during takeoff, resulting in a loss of engine thrust. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Propeller system](https://openairdocs.org/ntsb-findings/01046100): Aircraft › Aircraft propeller/rotor · Failure (probable cause); cases with it: [Mischke David BD-5B, 1 case](https://openairdocs.org/ntsb-findings/01046100/cases.md?model=056280E), [All aircraft, 20 cases](https://openairdocs.org/ntsb-findings/01046100/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Mischke David BD-5B, 1 case](https://openairdocs.org/ntsb-events/341/sequence.md?model=056280E), [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: [Mischke David BD-5B, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=056280E), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis The pilot reported that shortly after takeoff for the local area flight the engine's rpms decreased and he felt a loss of thrust. The pilot made a turn in an attempt to make an emergency landing to another runway; however, the airplane touched down hard and short of the runway, substantially damaging the airplane. Postaccident examination revealed that the sprag clutch failed, preventing the engine from turning the propeller and causing a loss of thrust. ## Factual narrative On October 14, 2010, at 1140 Pacific daylight time, an experimental Mischke BD-5D, N525BD, impacted the approach end of runway 22 at Skagit Regional Airport, Burlington, Washington. The commercial pilot was operating the airplane under the provisions of 14 Code of Federal Regulations Part 91. The pilot sustained serious injuries; the airplane was substantially damaged. Visual meteorological conditions prevailed and no flight plan was filed for the local area flight. The pilot submitted a written statement following the accident. After departing runway 10, the airplane rotated at 90 miles per hour (mph), he retracted the landing gear, and accelerated the airplane to 140 mph while climbing to 50 to 75 feet above ground level. The engine revolutions per minute (rpm) increased, then decreased from 9,000 to about 7,000, and he felt a loss of thrust in the airplane. He retarded the throttle and attempted an emergency landing on runway 22. The airplane landed hard short of the runway, with the landing gear retracted. The pilot reported that the airplane was powered by a Yamaha Nytro snowmobile engine rated at 130 horsepower at 10,000 rpm. The engine ran at 8,000 rpm with the propeller at 4,000 rpm. Examination of the drive system revealed that the sprag clutch that connected the drive system had failed and the engine lost thrust. A Dynon Avionics EFIS-D10A unit was recovered from the airplane and sent to the Safety Board Recorder Laboratory. Information regarding the flight track, ground, and altitude were obtained from the unit. Because the unit did not have a recent software upgrade, no additional information was recorded. ## Aircraft - Registration: [N525BD](https://openairdocs.org/deregistered/N525BD-2012-05-08), registration cancelled 2012-05-08, S/N 2, built 2009 (OpenAirDocs) - Reported make and model: MISCHKE BD-5B - Registry model: [Mischke David BD-5B](https://openairdocs.org/model/mischke-david-bd-5b) (registry code 056280E) (OpenAirDocs) - Registry engine: [Yamaha ALL MDLS A/B](https://openairdocs.org/engine/yamaha-all-mdls-a-b) (registry code 80000, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 2 - Airframe hours: 119 - Engines: YAMAHA Nytro 130 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: David Mischke - Registered owner: David Mischke - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, March 4, 2010, 67 hours before - Departed: BVS, Burlington, WA - Destination: BVS, Burlington, WA - Airport: BVS, Skagit Regional Airport, runway 22, 3,000 × 60 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 68; injuries: serious; commercial; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review February 23, 2008; seat: single; flight hours: 968 total, 229 in this make and model, 968 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: 240° at 9 knots - Visibility: 10 statute miles - Lowest ceiling: 1,400 ft broken - Temperature: 54 °F, dew point 50 °F - Altimeter: 30.12 inHg - Observed at: NUW, 12 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 20101014054449A](https://openairdocs.org/incident/20101014054449A), Oct 14, 2010: Mischke Dav BD-5B, Burlinton, WA, Substantial damage. On October 14, 2010, approximately 1140 pacific daylight time, at Skagit Regional Airport, burlington, WA. An amateur built experimental BD-5B took off from… ## Docket (6 files) The files NTSB released with the investigation on April 14, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=77584. 5.8 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 4.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40343325&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Pilot Record of Conversation (item 2, .PDF, 52 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40345688&FileExtension=.PDF&FileName=Pilot%20Record%20of%20Conversation-Master.PDF - Track Log File (item 3, .PDF, 99 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40345689&FileExtension=.PDF&FileName=Track%20Log%20File-Master.PDF - EFIS Information (3 embedded images) (item 4, .PDF, 3 photos, 424 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40345727&FileExtension=.PDF&FileName=EFIS%20Information%20(3%20embedded%20images)-Master.PDF - Photographs (2 embedded photos) (item 5, .PDF, 2 photos, 236 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40345700&FileExtension=.PDF&FileName=Photographs%20(2%20embedded%20photos)-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 6, .PDF, 83 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40345690&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-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.