# NTSB CEN21LA352: North American AT-6F, N6601C, Adrian, MI, July 28, 2021 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: July 28, 2021, 10:00 local (14:00 UTC) - Place: Adrian, MI - Coordinates: 41.867674, -84.077306 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.8677&lon=-84.0773&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-flare/touchdown: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Central Region - Parties: Federal Aviation Administration; East Michigan FSDO - NTSB case key (mKey): 103627 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN21LA352 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/103627/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=103627 - Page: https://openairdocs.org/ntsb/CEN21LA352 ## Probable cause The loss of control during landing due to the out of rig condition of the tailwheel which resulted in a ground loop and impact with the runway. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: nose/tail landing gear](https://openairdocs.org/ntsb-findings/01023220): Aircraft › Aircraft systems · Not specified (probable cause); cases with it: [North American AT-6F, 1 case](https://openairdocs.org/ntsb-findings/01023220/cases.md?model=6400420), [All aircraft, 185 cases](https://openairdocs.org/ntsb-findings/01023220/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-flare/touchdown: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [North American AT-6F, 1 case](https://openairdocs.org/ntsb-events/330/sequence.md?model=6400420), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Landing-landing roll: Loss of control on ground](https://openairdocs.org/ntsb-events/230); cases with it: [North American AT-6F, 2 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=6400420), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Landing-landing roll: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [North American AT-6F, 2 cases](https://openairdocs.org/ntsb-events/060/sequence.md?model=6400420), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md) - [Landing-landing roll: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [North American AT-6F, 3 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=6400420), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis The pilot receiving instruction during the instructional flight reported that he performed a wheel landing and the airplane touched down on the runway centerline. After the tailwheel touched down onto the runway, the airplane began to track to the left. The pilot began to apply increasing right rudder control input, but the airplane continued to track left. He then applied right “differential steering” and the airplane overshot the runway centerline, tracking right. He was unable to arrest the right track with full left rudder control input and left brake, and the airplane ground looped. The left landing gear collapsed, and the left wing struck the ground. The airplane sustained substantial damage to the left wing spar. A postaccident examination of the airplane revealed that the tailwheel was out of rigging specifications, which would have resulted in a loss of directional control during landing. ## Factual narrative The pilot receiving instruction during the instructional flight stated that he performed a wheel landing and the airplane touched down on the runway centerline. After the tailwheel touched down onto the runway, the airplane began to track left. The pilot began to apply increasing right rudder control input, but the airplane continued to track left. He then applied right “differential steering” and the airplane overshot the runway centerline, tracking right. He was unable to arrest the right track with full left rudder control input and left brake. The airplane ground looped, the left landing gear collapsed, and the left wing struck the ground resulting in substantial damage to the left wing spar. Postaccident examination of the airplane revealed that the tailwheel was out of rigging specifications, which would have resulted in a loss of directional control during landing. ## Aircraft - Registration: [N6601C](https://openairdocs.org/aircraft/N6601C), registered now, S/N 121-42479, built 1957 (OpenAirDocs) - Reported make and model: NORTH AMERICAN AT-6F - Registry model: [North American AT-6F](https://openairdocs.org/model/north-american-at-6f) (registry code 6400420) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 121-42479 - Year built: 1957 - Airframe hours: 5614 - Engines: Pratt & Whitney R1340-AN-1 reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: B&S Aviation - Airworthiness certificate: Standard, Normal - Last inspection: 100 hour, July 27, 2021 - Departed: DUH, Ottawa Lake, OH - Destination: Same as departure - Airport: ADG, Lenawee County Airport, runway 23, 5,001 × 100 ft, asphalt - Equipment: ADS-B ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 61; injuries: none; private; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review July 14, 2021; seat: front; restraint: 5-point; flight hours: 4,267 total, 14 in this make and model, 41 in the last 90 days, 12 in the last 30 days - Flight instructor; injuries: none; commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: unknown; seat: rear; flight hours: 20,000 total, 150 in this make and model, 20 in the last 90 days ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 84 °F, dew point 66 °F - Altimeter: 30.06 inHg - Observed at: ADG ## 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 20210728019929A](https://openairdocs.org/incident/20210728019929A), Jul 28, 2021: North American AT-6F, Adrian, MI, Substantial damage. From the pilot: the landing was a normal centerline wheel landing. After the tailwheel settled the aircraft started tracking left. I applied increasing right… ## Docket (4 files) The files NTSB released with the investigation on February 28, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=103627. 1.6 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 706 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13267567&FileExtension=pdf&FileName=Rstansley%20NTSB%20Report_Redacted-Rel.pdf - Pilot statement (item 2, PDF, 1 page, 92 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13267074&FileExtension=pdf&FileName=Pilot%20Statement%20N6601C_Redacted-Rel.pdf - Flight instructor statement (item 3, PDF, 2 pages, 159 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13271352&FileExtension=pdf&FileName=Statement%20FW_%20T-6%20at%20Adrian_Redacted-Rel.pdf - Photo log (item 4, PDF, 2 pages, 662 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13267791&FileExtension=pdf&FileName=Photo%20Log-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.