# NTSB WPR22LA085: Universal Stinson 108-2, N9433K, Byron, CA, January 27, 2022

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Class 4 · Limited · Final report
- Date: January 27, 2022, 14:45 local (22:45 UTC)
- Place: Byron, CA
- Coordinates: 37.4973, -121.3758
- Nearby events: https://openairdocs.org/map.md?lat=37.4973&lon=-121.3758&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: 2 uninjured
- Status: Completed
- Report: Approved by Office Director
- Investigation class: Class 4 - Basic report with no Prelim publish
- NTSB office: Western Pacific Region
- Parties: FAA FSDO
- NTSB case key (mKey): 104564
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR22LA085
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/104564/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=104564
- Page: https://openairdocs.org/ntsb/WPR22LA085

## Probable cause

The pilot’s inadequate flare and loss of directional control during landing which resulted in a runway excursion. Contributing to the accident was the instructor’s delayed remedial action.

## 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: [Universal Stinson 108-2, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=9230416), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md)
- [Action: delayed action](https://openairdocs.org/ntsb-findings/02041025): Personnel issues › Action/decision · Instructor/check pilot (probable cause); cases with it: [Universal Stinson 108-2, 2 cases](https://openairdocs.org/ntsb-findings/02041025/cases.md?model=9230416), [All aircraft, 894 cases](https://openairdocs.org/ntsb-findings/02041025/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: [Universal Stinson 108-2, 1 case](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=9230416), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md)
- [Info processing/decision: decision making/judgment](https://openairdocs.org/ntsb-findings/02041520): Personnel issues › Action/decision · Pilot (probable cause); cases with it: [Universal Stinson 108-2, 1 case](https://openairdocs.org/ntsb-findings/02041520/cases.md?model=9230416), [All aircraft, 3,098 cases](https://openairdocs.org/ntsb-findings/02041520/cases.md)
- [Performance/control parameters: landing flare](https://openairdocs.org/ntsb-findings/01062041): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Universal Stinson 108-2, 1 case](https://openairdocs.org/ntsb-findings/01062041/cases.md?model=9230416), [All aircraft, 1,285 cases](https://openairdocs.org/ntsb-findings/01062041/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: [Universal Stinson 108-2, 1 case](https://openairdocs.org/ntsb-events/230/sequence.md?model=9230416), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md)
- [Landing-flare/touchdown: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Universal Stinson 108-2, 1 case](https://openairdocs.org/ntsb-events/060/sequence.md?model=9230416), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md)
- [Landing-landing roll: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Universal Stinson 108-2, 2 cases](https://openairdocs.org/ntsb-events/300/sequence.md?model=9230416), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md)

## Analysis

The flight instructor of a tail wheel equipped airplane reported that, while practicing touch-and-go landings the pilot receiving instruction made a landing which resulted in a “medium bounce”. During the second flare the airplane immediately yawed left. The pilot corrected to the right and back to the left. The flight instructor tried to intervene; however, the airplane exited the side of the runway. The left wing was substantially damaged. The flight instructor reported that there were no preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation.

## Aircraft

- Registration: [N9433K](https://openairdocs.org/aircraft/N9433K), registered now, S/N 1082433, built 1947 (OpenAirDocs)
- Reported make and model: UNIVERSAL STINSON 108-2
- Registry model: [Universal Stinson 108-2](https://openairdocs.org/model/universal-stinson-108-2) (registry code 9230416) (OpenAirDocs)
- Registry engine: [Franklin 6A4165 series](https://openairdocs.org/engine/franklin-6a4165-series) (registry code 27025, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 1082433
- Year built: 1947
- Airframe hours: 2813.2
- Engines: FRANKLIN GA4-165 SERIES B3 165 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Dale Zapara
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, October 12, 2021
- Departed: KSCK, Stockton, CA
- Destination: C83, Byron, CA
- Airport: C83, Byron, runway 30, 4,500 × 100 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 74; injuries: none; private; airplane ratings: single-engine land; medical: class 3, unknown; seat: left; restraint: lap only; flight hours: 108 total, 57 in this make and model
- Flight instructor; age 72; injuries: none; airline transport, flight instructor, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1; last flight review November 9, 2021; seat: right; restraint: lap only; flight hours: 16,300 total, 57 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Lowest ceiling: none
- Temperature: 63 °F
- Altimeter: 29.92 inHg
- Observed at: KSCK C83, 0.1 nm away
- METAR: 
METAR KSCK 272055Z 00000KT 10SM CLR 16/03 A3023 RMK AO2 SLP236 T01610033 58010=

## 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 20220127001209A](https://openairdocs.org/incident/20220127001209A), Jan 27, 2022: Universal Stinson 108-2, Byron, CA, Substantial damage. Aircraft was landing runway 30 at C83 Byron, CA. Aircraft touched down in 3-point configuration and began to veer left. The pilot in the left seat attempted to…

## Docket (2 files)

The files NTSB released with the investigation on April 19, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=104564. 3.5 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13320399&FileExtension=pdf&FileName=NTSB%20Form%206120_1%20(1)master_Redactedflat-Rel.pdf
- Photos (item 2, PDF, 4 pages, 4 photos, 1.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13319969&FileExtension=pdf&FileName=Photo%201-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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