# NTSB WPR21LA197: Stearman 4E, N663K, Porterville, CA, May 17, 2021

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Class 4 · Limited · Final report
- Date: May 17, 2021, 14:30 local (21:30 UTC)
- Place: Porterville, CA · Airport
- Coordinates: 36.029583, -119.06272
- Nearby events: https://openairdocs.org/map.md?lat=36.0296&lon=-119.0627&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Defining event: [Landing: 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: Western Pacific Region
- Parties: FAA
- NTSB case key (mKey): 103101
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR21LA197
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/103101/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=103101
- Page: https://openairdocs.org/ntsb/WPR21LA197

## Probable cause

The pilot’s loss of directional control while landing, which resulted in a landing gear collapse.

## 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: [Stearman 4E, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=8560306), [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: [Stearman 4E, 1 case](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=8560306), [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: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Stearman 4E, 1 case](https://openairdocs.org/ntsb-events/230/sequence.md?model=8560306), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md)
- [Landing: Landing gear collapse](https://openairdocs.org/ntsb-events/094); cases with it: [Stearman 4E, 1 case](https://openairdocs.org/ntsb-events/094/sequence.md?model=8560306), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md)

## Analysis

The pilot of the tailwheel equipped airplane reported that, after landing the airplane encountered a gust of wind and ballooned. During the subsequent touch down, the airplane landed “in a very minor crab,” the right main landing gear collapsed, and the lower right wing was substantially damaged when it impacted the runway surface. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation.

## Aircraft

- Registration: [N663K](https://openairdocs.org/aircraft/N663K), registered now, S/N 4005, built 1930 (OpenAirDocs)
- Reported make and model: STEARMAN AIRCRAFT 4E
- Registry model: [Stearman 4E](https://openairdocs.org/model/stearman-4e) (registry code 8560306) (OpenAirDocs)
- Registry engine: [Pratt & Whitney W-SC series](https://openairdocs.org/engine/pratt-whitney-w-sc-series) (registry code 52010, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 4005
- Year built: 1930
- Engines: Pratt & Whitney R-1340 SC-1 450 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: William Ben Scott
- Registered owner: William Ben Scott
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, March 31, 2021
- Departed: KSEE, San Diego, CA
- Destination: Same as departure
- Airport: PTV, Porterville Muni, runway 30, 5,960 × 150 ft, asphalt
- Equipment: ADS-B

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 62; injuries: none; flight instructor, commercial, flight engineer, airline transport; airplane ratings: multi-engine land, single-engine land, single-engine sea; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review March 15, 2021; seat: rear; flight hours: 28,462 total, 126 in this make and model, 11,500 as pilot in command, 165 in the last 90 days, 61 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 290° at 7 knots
- Visibility: 10 statute miles
- Temperature: 84 °F, dew point 52 °F
- Altimeter: 29.97 inHg
- Observed at: KPTV
- METAR: KPTV 172156Z AUTO 29007KT 260V320 10SM CLR 29/11 A2997 RMK AO2 SLP145 T02890111

## 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 20210517006229A](https://openairdocs.org/incident/20210517006229A), May 17, 2021: Stearman Aircraft 4E, Porterville, CA, Substantial damage. On June 17, 2021, N663K a Stearman Aircraft A4 was involved in a accident while attempting a landing on runway 30 at the Porterville Municipal Airport at…

## Other investigations on N663K (1)

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.

- [NTSB SEA90LA059](https://openairdocs.org/ntsb/SEA90LA059), Mar 31, 1990: Stearman 4E (N663K), Burns, OR, substantial damage. Probable cause: THE PILOT'S FAILURE TO MAINTAIN DIRECTIONAL CONTROL.

## Docket (3 files)

The files NTSB released with the investigation on September 1, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=103101. 2.0 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 9 pages, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12310570&FileExtension=pdf&FileName=WPR21LA197%20Pilot%206120_Redacted-Rel.pdf
- Record of e-mail correspondence (pilot) (item 2, PDF, 1 page, 165 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12311262&FileExtension=pdf&FileName=Record%20of%20e-mail%20correspondence%20(pilot)-Rel.pdf
- Damage photo (item 3, PDF, 1 page, 337 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12310259&FileExtension=pdf&FileName=Damage%20Photo-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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