# NTSB ERA21LA027: Muse Stol CH 750, N750JD, Sewanee, TN, October 14, 2020 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Class 4 · Limited · Final report - Date: October 14, 2020, 13:03 local (18:03 UTC) - Place: Sewanee, TN - Coordinates: 35.208012, -85.89325 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.2080&lon=-85.8932&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Eastern Region Aviation - Parties: FAA - NTSB case key (mKey): 102168 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA21LA027 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/102168/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=102168 - Page: https://openairdocs.org/ntsb/ERA21LA027 ## Probable cause The airplane’s encounter with a downdraft during the initial climb, which resulted in an impact with trees. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: climb rate](https://openairdocs.org/ntsb-findings/01062035): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible (probable cause); cases with it: [Muse David A STOL CH 750, 1 case](https://openairdocs.org/ntsb-findings/01062035/cases.md?model=05635DC), [All aircraft, 265 cases](https://openairdocs.org/ntsb-findings/01062035/cases.md) - [Turbulence: terrain induced turbulence](https://openairdocs.org/ntsb-findings/03032010): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Muse David A STOL CH 750, 1 case](https://openairdocs.org/ntsb-findings/03032010/cases.md?model=05635DC), [All aircraft, 70 cases](https://openairdocs.org/ntsb-findings/03032010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Muse David A STOL CH 750, 1 case](https://openairdocs.org/ntsb-events/400/sequence.md?model=05635DC), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) - [Initial climb: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) (defining event); cases with it: [Muse David A STOL CH 750, 1 case](https://openairdocs.org/ntsb-events/490/sequence.md?model=05635DC), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md) ## Analysis The pilot was taking off from a 3,700-ft-long runway and described that during the initial climb at an altitude of around 40 feet, the airplane encountered a downdraft from wind gusting over trees next to the runway. He further reported that the engine was developing full power, but the airplane was unable to climb out of the downdraft. The airplane impacted trees at the departure end of the runway, and the fuselage and right wing were substantially damaged. The pilot reported that there were no preimpact mechanical failures or malfunctions of the airplane that would have precluded normal operation. ## Aircraft - Registration: [N750JD](https://openairdocs.org/deregistered/N750JD-2021-01-25), registration cancelled 2021-01-25, S/N 75-8735 (OpenAirDocs) - Reported make and model: Muse STOL CH 750 - Registry model: [Muse David A STOL CH 750](https://openairdocs.org/model/muse-david-a-stol-ch-750) (registry code 05635DC) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 75-8735 - Year built: 2016 - Airframe hours: 50 - Engines: General Motors 167.C.I. 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, October 8, 2020, 45.6 hours before - Destination: 2A0, Dayton, TN - Airport: UOS, Franklin County Airport, runway 6, 3,700 × 50 ft, asphalt - Equipment: Electronic flight bag or handheld device, Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 73; injuries: minor; sport pilot; airplane ratings: single-engine land; medical: sport pilot; seat: left; restraint: 3-point; flight hours: 159.3 total, 97.8 in this make and model, 7.4 in the last 90 days, 7.4 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 170° at 6 knots, gusting 12 - Visibility: 10 statute miles - Temperature: 75 °F, dew point 46 °F - Altimeter: 30.05 inHg - Turbulence: Unknown - Observed at: KBGF, 9 nm away - METAR: KBGF 141755Z AUTO 17006G12KT 10SM CLR 24/08 A3005 RMK A01 ## 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 20201014015479A](https://openairdocs.org/incident/20201014015479A), Oct 14, 2020: Muse David A STOL CH 750, Sewanee, TN, Substantial damage. PIC departed uos with an airmet-t valid. Winds were reported calm by the pilot but he said it was gusty above the trees. PIC departed off runway 06 and… ## Docket (4 files) The files NTSB released with the investigation on June 24, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=102168. 6.2 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 5.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11566315&FileExtension=pdf&FileName=Signed%206120_Redacted-Rel.pdf - Pilot interview summary (item 2, PDF, 3 pages, 56 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11566072&FileExtension=pdf&FileName=Record%20of%20Conversation%20w%20David%20Muse_Redacted-Rel.pdf - Area weather reports (item 3, PDF, 1 page, 81 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11566219&FileExtension=pdf&FileName=Area%20Weather%20Reports-Rel.pdf - Investigative photographs (item 4, PDF, 5 pages, 682 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11566357&FileExtension=pdf&FileName=ERA21LA027%20Photo%20Array-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.