# NTSB CEN21LA288: Vining SD1 Minisport, N72DX, Butler, OH, June 23, 2021 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: June 23, 2021, 10:15 local (14:15 UTC) - Place: Butler, OH · cornfield adjacent to grass runway - Coordinates: 40.59683, -82.43173 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=40.5968&lon=-82.4317&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Loss of control in flight](https://openairdocs.org/ntsb-events/240) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Central Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 103321 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN21LA288 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/103321/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=103321 - Page: https://openairdocs.org/ntsb/CEN21LA288 ## Probable cause The pilot’s failure to maintain adequate airspeed following a partial loss of engine power, which resulted in an aerodynamic stall and impact with terrain. The reason for the partial loss of engine power could not be determined based on available information. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating)](https://openairdocs.org/ntsb-findings/01058500): Aircraft › Aircraft power plant · Unknown/Not determined (probable cause); cases with it: [Vining John K SD-1 MINISPORT, 1 case](https://openairdocs.org/ntsb-findings/01058500/cases.md?model=056350E), [All aircraft, 497 cases](https://openairdocs.org/ntsb-findings/01058500/cases.md) - [Wind: crosswind](https://openairdocs.org/ntsb-findings/03034040): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Vining John K SD-1 MINISPORT, 1 case](https://openairdocs.org/ntsb-findings/03034040/cases.md?model=056350E), [All aircraft, 1,008 cases](https://openairdocs.org/ntsb-findings/03034040/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Vining John K SD-1 MINISPORT, 1 case](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=056350E), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Vining John K SD-1 MINISPORT, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=056350E), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Vining John K SD-1 MINISPORT, 1 case](https://openairdocs.org/ntsb-events/400/sequence.md?model=056350E), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) - [Takeoff: Unknown or undetermined](https://openairdocs.org/ntsb-events/000); cases with it: [Vining John K SD-1 MINISPORT, 1 case](https://openairdocs.org/ntsb-events/000/sequence.md?model=056350E), [All aircraft, 1,703 cases](https://openairdocs.org/ntsb-events/000/sequence.md) - [Takeoff: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342); cases with it: [Vining John K SD-1 MINISPORT, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=056350E), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Takeoff: Loss of control in flight](https://openairdocs.org/ntsb-events/240) (defining event); cases with it: [Vining John K SD-1 MINISPORT, 1 case](https://openairdocs.org/ntsb-events/240/sequence.md?model=056350E), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) ## Analysis A line of trees paralleled the runway on the southwest side, and a cornfield was on the northeast side. As the pilot taxied to the end of runway 13, he noted a significant crosswind from over the tree line. After a normal runup, he increased to full power. Immediately after the airplane lifted off the ground, it drifted to the right over the cornfield. The airplane “seemed to have too little power to climb” and the airplane stalled, touching down in the field. The left main landing gear separated, and the airplane spun to a stop. A postaccident examination of the engine revealed a crack in the pressure vacuum line; however, it could not be determined whether the crack could have caused a reduction in engine power. The circumstances of the accident are consistent with the pilot’s failure to maintain adequate airspeed following a partial loss of engine power during takeoff, which resulted in an aerodynamic stall. ## Factual narrative On June 23, 2021, at 1015 eastern daylight time, an experimental amateur-built SD-1 Minisport airplane, N72DX, was substantially damaged when it was involved in an accident at Freeman Swank Farms Airport (0OH5), Butler, Ohio. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. A line of trees paralleled the runway on the southwest side of the runway, and a cornfield was on the northeast side. As the pilot taxied to the end of runway 13, he noted a significant crosswind from over the tree line. After a normal runup, he increased the engine to full power. Immediately after the airplane lifted off the ground it drifted to the right over the cornfield. The airplane “seemed to have too little power to climb” and it stalled, touching down in the field. The left main landing gear separated, and the airplane spun to a stop. The airplane’s left-wing spar was substantially damaged. The fuel tank remained intact and about 7-8 gallons remained inside. The spark plugs were removed from the engine and were consistent with normal operations. The engine rotated without binding, and thumb compression was established on all cylinders. A boroscope was used to examine the inside of the cylinders; the piston heads and cylinder walls exhibited normal operating wear signatures. The pressure vacuum line exhibited a crack near where it connects to the engine. The crack was not visible until the protective sleeve was removed from the line. The nearest weather reporting facility was located about 14 miles north of the accident airport. At 0952, wind was reported from 220° at 6 knots. At 1100, the National Weather Service Surface Analysis Chart depicted southwest winds at 5 to 10 knots. ## Aircraft - Registration: [N72DX](https://openairdocs.org/aircraft/N72DX), registered now, S/N 0194, built 2017 (OpenAirDocs) - Reported make and model: VINING SD1 MINISPORT - Registry model: [Vining John K SD-1 MINISPORT](https://openairdocs.org/model/vining-john-k-sd-1-minisport) (registry code 056350E) (OpenAirDocs) - Registry engine: [Hirth F-23](https://openairdocs.org/engine/hirth-f-23) (registry code 33721, 2 cycle) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 0194 - Year built: 2017 - Airframe hours: 31 - Engines: Hirth F23 50 hp reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental light sport (Special) - Last inspection: Annual, October 25, 2020, 7 hours before - Destination: 4I3, Mount Vernon, OH - Airport: 0OH5, Freeman Swank Farms Airport, runway 13, 3,002 × 100 ft, grass/turf - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 67; injuries: none; private; airplane ratings: single-engine land; medical: sport pilot; seat: single; restraint: 4-point; flight hours: 365 total, 29 in this make and model, 330 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: 220° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 68 °F, dew point 45 °F - Altimeter: 30.20 inHg - Observed at: KMFD, 14 nm away - METAR: ## 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 20210623011889A](https://openairdocs.org/incident/20210623011889A), Jun 23, 2021: Vining John K SD-1 MINISPORT, Butler, OH, Substantial damage. Approximately 1000 on 6/23/2021, aircraft N72DX, an amateur kit built, SD-1 minisport, attempted taking off on a grass strip runway 13 (east) at 0OH5 (Butler,… ## Docket (5 files) The files NTSB released with the investigation on June 21, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=103321. 8.7 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 6 pages, 3.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12581725&FileExtension=pdf&FileName=6120%20printed2_Redacted-Rel.pdf - On scene photos - courtsey of the federal aviation administration (item 2, PDF, 2 pages, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12582038&FileExtension=pdf&FileName=on%20scene%20photos-Rel.pdf - Postaccident engine examination (item 3, PDF, 5 pages, 2.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12641624&FileExtension=pdf&FileName=roc%20faa%20engine%20exam%208.11.21-Rel.pdf - Record of email a�� meteorology (item 4, PDF, 2 pages, 416 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12581561&FileExtension=pdf&FileName=ROE%20WX-Rel.pdf - Google earth photo of airport (item 5, PDF, 1 page, 716 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12581462&FileExtension=pdf&FileName=google%20earth%20photo%20of%20runway-Rel.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.