# NTSB GAA19CA479: Schleicher ASW 27, N274JM, Mackay, ID, July 27, 2019 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: July 27, 2019, 16:15 local (22:15 UTC) - Place: Mackay, ID - Coordinates: 43.853332, -113.512779 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.8533&lon=-113.5128&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report December 2, 2019 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 99992 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA19CA479 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/99992/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=99992 - Page: https://openairdocs.org/ntsb/GAA19CA479 ## Probable cause The pilot's failure to maintain lateral control of the glider during landing in gusting wind conditions, which resulted in the left wing striking the ground and a subsequent ground loop. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: lateral/bank control](https://openairdocs.org/ntsb-findings/01062023): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Schleicher ASW-27, 2 cases](https://openairdocs.org/ntsb-findings/01062023/cases.md?model=3801501), [All aircraft, 390 cases](https://openairdocs.org/ntsb-findings/01062023/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Schleicher ASW-27, 4 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=3801501), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Wind: gusts](https://openairdocs.org/ntsb-findings/03034045): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Schleicher ASW-27, 3 cases](https://openairdocs.org/ntsb-findings/03034045/cases.md?model=3801501), [All aircraft, 1,199 cases](https://openairdocs.org/ntsb-findings/03034045/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Approach: Loss of lift](https://openairdocs.org/ntsb-events/500); cases with it: [Schleicher ASW-27, 5 cases](https://openairdocs.org/ntsb-events/500/sequence.md?model=3801501), [All aircraft, 252 cases](https://openairdocs.org/ntsb-events/500/sequence.md) - [Landing-landing roll: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Schleicher ASW-27, 5 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=3801501), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-landing roll: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Schleicher ASW-27, 6 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=3801501), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Landing-landing roll: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Schleicher ASW-27, 2 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=3801501), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Landing-landing roll: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Schleicher ASW-27, 1 case](https://openairdocs.org/ntsb-events/400/sequence.md?model=3801501), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) ## Analysis The pilot reported that, while returning to the airport, the glider descended faster than expected, so he diverted to a field for landing. The glider encountered a wind gust, and the left wing hit the ground. The glider then ground looped to the left. The glider sustained substantial damage to the fuselage, empennage, and right aileron. The pilot reported that there were no preaccident mechanical failures or malfunctions with the glider that would have precluded normal operation. The pilot reported that the wind was from 140°, between about 10 and 20 knots, and gusting. The pilot landed the glider to the south. ## Factual narrative The pilot of the glider reported that, while returning to the airport, the glider descended faster than expected, so he diverted to an alfalfa field for landing. The glider encountered a gust of wind and the left wing "suddenly" hit the ground. The glider then ground looped to the left. The glider sustained substantial damage to the fuselage, empennage and right aileron. The pilot reported that there were no preaccident mechanical failures or malfunctions with the glider that would have precluded normal operation. The pilot reported that the wind was from 140° at 10 to 20 knots and gusting. The pilot landed the glider to the south. ## Aircraft - Registration: [N274JM](https://openairdocs.org/aircraft/N274JM), registered now, S/N 27029 (OpenAirDocs) - Reported make and model: Schleicher ASW 27 (Undesignat) - Registry model: [Schleicher ASW-27](https://openairdocs.org/model/schleicher-asw-27) (registry code 3801501) (OpenAirDocs) - Category: Glider - Serial number: 27029 - Year built: 1986 - Airframe hours: 1408 - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, October 19, 2018 - Departed: U62, Mackay, ID - Destination: U62, Mackay, ID - Equipment: Electronic primary flight display, Data recorder ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 74; injuries: none; flight instructor, commercial; last flight review October 18, 2018; seat: single; restraint: 4-point; flight hours: 3,164 total, 1,130 in this make and model, 3,164 as pilot in command, 82 in the last 90 days, 42 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 260° at 8 knots, gusting 14 - Visibility: 10 statute miles - Temperature: 84 °F, dew point 45 °F - Altimeter: 30.18 inHg - Turbulence: Moderate - Observed at: KSUN, 40 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 20190727016719A](https://openairdocs.org/incident/20190727016719A), Jul 27, 2019: Schleicher ASW-27, Mackay, ID, Substantial damage. The pilot was soaring back from the king mountain area to the Mackay Airport, a distance of about 18 miles. The pilot stated that he had enough altitude to… ## Docket (2 files) The files NTSB released with the investigation on October 3, 2019, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=99992. 2.9 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476411&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Damage Photos (item 2, .PDF, 2 photos, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40476412&FileExtension=.PDF&FileName=Damage%20Photos-Master.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.