# NTSB WPR23LA266: Piper PA-12, N4135M, Judith Gap, MT, July 8, 2023

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Class 4 · Limited · Final report
- Date: July 8, 2023, 14:00 local (20:00 UTC)
- Place: Judith Gap, MT · Open field
- Coordinates: 46.65948, -109.74389 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=46.6595&lon=-109.7439&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Defining event: [Takeoff: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490)
- Highest injury: Minor injuries
- Injuries: 1 minor, 1 uninjured
- Status: Completed
- Report: Approved by Office Director
- Investigation class: Class 4 - Basic report with no Prelim publish
- NTSB office: Western Pacific Region
- Parties: Federal Aviation Administration
- NTSB case key (mKey): 192584
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR23LA266
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/192584/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=192584
- Page: https://openairdocs.org/ntsb/WPR23LA266

## Probable cause

The pilot's decision to take off on a soft field that exceeded the performance capabilities of the airplane, which resulted in an impact with a pole and terrain.

## Findings

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

- [Aircraft capability: takeoff distance](https://openairdocs.org/ntsb-findings/01061025): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause); cases with it: [Piper PA-12, 2 cases](https://openairdocs.org/ntsb-findings/01061025/cases.md?model=7101202), [All aircraft, 67 cases](https://openairdocs.org/ntsb-findings/01061025/cases.md)
- [Object/animal/substance: pole](https://openairdocs.org/ntsb-findings/03022010): Environmental issues › Physical environment · Effect on operation; cases with it: [Piper PA-12, 1 case](https://openairdocs.org/ntsb-findings/03022010/cases.md?model=7101202), [All aircraft, 142 cases](https://openairdocs.org/ntsb-findings/03022010/cases.md)
- [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot; cases with it: [Piper PA-12, 51 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7101202), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md)
- [Runway/land/takeoff/taxi surface: soft surface](https://openairdocs.org/ntsb-findings/03023020): Environmental issues › Physical environment · Effect on operation; cases with it: [Piper PA-12, 3 cases](https://openairdocs.org/ntsb-findings/03023020/cases.md?model=7101202), [All aircraft, 264 cases](https://openairdocs.org/ntsb-findings/03023020/cases.md)
- [Temp/humidity/pressure: high density altitude](https://openairdocs.org/ntsb-findings/03031020): Environmental issues › Conditions/weather/phenomena · Effect on operation; cases with it: [Piper PA-12, 2 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md?model=7101202), [All aircraft, 278 cases](https://openairdocs.org/ntsb-findings/03031020/cases.md)

## Sequence of events

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

- [Takeoff: Collision during takeoff/land](https://openairdocs.org/ntsb-events/490) (defining event); cases with it: [Piper PA-12, 9 cases](https://openairdocs.org/ntsb-events/490/sequence.md?model=7101202), [All aircraft, 1,309 cases](https://openairdocs.org/ntsb-events/490/sequence.md)

## Analysis

The pilot reported that he “failed to recon” the field he had just landed on. During his departure attempt, high density altitude and soft ground led to a longer than expected takeoff roll. While maneuvering to avoid a bank on the opposite side of a road the airplane struck a power pole resulting in substantial damage to the right wing. The pilot reported no preimpact mechanical failures or malfunctions with the airplane that would have precluded normal operation.

## Aircraft

- Registration: [N4135M](https://openairdocs.org/aircraft/N4135M), registered now, S/N 12-3034, built 1947 (OpenAirDocs)
- Reported make and model: PIPER PA-12
- Registry model: [Piper PA-12](https://openairdocs.org/model/piper-pa-12) (registry code 7101202) (OpenAirDocs)
- Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs)
- Category: Airplane
- Serial number: 12-3034
- Year built: 1947
- Airframe hours: 2534.5
- Engines: LYCOMING O-235 SERIES 115 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, July 1, 2022
- Departed: KLWT, Lewistown, MT
- Airport: NA
- Equipment: ADS-B, Handheld GPS

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 57; injuries: minor; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review November 19, 2021; seat: front; restraint: 4-point; flight hours: 350 total, 240 in this make and model, 148 as pilot in command, 18 in the last 90 days, 0 in the last 30 days, 0 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Visibility: 10 statute miles
- Temperature: 75 °F, dew point 46 °F
- Altimeter: 30.01 inHg
- Observed at: KLWT, 26 nm away
- METAR: KLWT 082054Z AUTO 14009KT 10SM SCT075 24/08 A3001 RMK AO2 LTG DSNT SE AND S SLP128 T02440078 57007

## 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 20230708008519A](https://openairdocs.org/incident/20230708008519A), Jul 8, 2023: Piper PA-12, Judith Gap, MT, Substantial damage. Pilot struck an electrical line support pole with right wing, rotated and continued backwards until impacting the ground and rolling into a small cow pond.

## Docket (2 files)

The files NTSB released with the investigation on November 2, 2023, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=192584. 2.5 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 2.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15998670&FileExtension=pdf&FileName=6120%20%20Judith%20Gap,%20MT%20N4135M_Redacted-Rel.pdf
- Photos (item 2, PDF, 1 page, 414 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16170311&FileExtension=pdf&FileName=Photo%20WPR23LA266-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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