# NTSB ERA21LA095: Cessna 170, N4580C, Madisonville, TN, December 22, 2020

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Class 4 · Limited · Final report
- Date: December 22, 2020, 15:30 local (20:30 UTC)
- Place: Madisonville, TN
- Coordinates: 35.543597, -84.382684 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=35.5436&lon=-84.3827&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: 3 uninjured
- Status: Completed
- Report: Approved by Office Director
- Investigation class: Class 4 - Basic report with no Prelim publish
- NTSB office: Eastern Region Aviation
- Parties: FAA/FSDO
- NTSB case key (mKey): 102478
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA21LA095
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/102478/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=102478
- Page: https://openairdocs.org/ntsb/ERA21LA095

## Probable cause

The pilot's failure to maintain directional control during the landing rollout, which resulted in a ground loop.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Cessna 170B, 91 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=2072306), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md)
- [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Cessna 170B, 74 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=2072306), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Landing-landing roll: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Cessna 170B, 84 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=2072306), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md)
- [Landing-landing roll: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Cessna 170B, 37 cases](https://openairdocs.org/ntsb-events/300/sequence.md?model=2072306), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md)

## Analysis

The pilot was landing his tailwheel-equipped airplane. He reported that after touchdown the airplane veered to the left. He applied right rudder and added power to correct; however, the airplane exited the runway and entered a ground loop. The airplane sustained substantial damage to the right wing. The pilot reported no preaccident mechanical failures or malfunctions of the airplane that would have precluded normal operation.

## Aircraft

- Registration: [N4580C](https://openairdocs.org/deregistered/N4580C-2021-07-31), registration cancelled 2021-07-31, S/N 25524, built 1953 (OpenAirDocs)
- Reported make and model: CESSNA 170 (B)
- Registry model: [Cessna 170B](https://openairdocs.org/model/cessna-170b) (registry code 2072306) (OpenAirDocs)
- Registry engine: [Continental C145 series](https://openairdocs.org/engine/continental-c145-series) (registry code 17012, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 25524
- Year built: 1953
- Airframe hours: 5667.45
- Engines: CONT MOTOR C145-2 145 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: East Tennessee Pilots Club Inc
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, March 14, 2020, 93.95 hours before
- Departed: TN98, Knoxville, TN
- Destination: Same as departure
- Airport: MNV, Monroe County, runway 5, 3,643 × 75 ft, asphalt
- Equipment: ADS-B, Stall warning system

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 61; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; seat: left; restraint: 4-point; flight hours: 170 total, 37 in this make and model, 37 as pilot in command, 13 in the last 90 days, 4 in the last 30 days, 0 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 54 °F, dew point 25 °F
- Altimeter: 30.25 inHg
- Observed at: MNV
- METAR: KTYS 221953Z 00000KT 10SM CLR 12/M04 A3023 RMK AO2 SLP239 T01171039 $

## 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 20201222020389A](https://openairdocs.org/incident/20201222020389A), Dec 22, 2020: Cessna 170B, Madisonville, TN, Substantial damage. After aircraft touchdown aircraft veered left off of the runway and ground looped. The right main gear departed the aircraft after departing the runway.

## Docket (4 files)

The files NTSB released with the investigation on July 8, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=102478. 5.1 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 2.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11792061&FileExtension=pdf&FileName=ERA21LA095%206120_Redacted-Rel.pdf
- Pilot's statement (item 2, PDF, 1 page, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11792431&FileExtension=pdf&FileName=Pilot%20Statement_Redacted-Rel.pdf
- FAA inspector statement (item 3, PDF, 1 page, 175 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11791775&FileExtension=pdf&FileName=Memorandum%20for%20Record-ROC%20ASI-Rel.pdf
- Photo array (item 4, PDF, 5 pages, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11792130&FileExtension=pdf&FileName=Photo%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.

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