# NTSB WPR25LA165: Weatherly 620B, N90393, Lewiston, MT, May 30, 2025

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Class 4 · Limited · Final report
- Date: May 29, 2025, 19:00 local (May 30, 2025, 01:00 UTC)
- Place: Lewiston, MT · Open field
- Coordinates: 47, -109 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.0000&lon=-109.0000&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Defining event: [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report September 26, 2025
- 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): 200245
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR25LA165
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/200245/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=200245
- Page: https://openairdocs.org/ntsb/WPR25LA165

## Probable cause

The pilot’s failure to maintain clearance from terrain while maneuvering at a low altitude.

## Findings

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

- [Attention/monitoring: monitoring environment](https://openairdocs.org/ntsb-findings/02021545): Personnel issues › Psychological · Pilot (probable cause); cases with it: [Weatherly 620B, 4 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md?model=9630605), [All aircraft, 809 cases](https://openairdocs.org/ntsb-findings/02021545/cases.md)
- [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Weatherly 620B, 5 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=9630605), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md)

## Sequence of events

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

- [Maneuvering-low-alt flying: Low altitude operation/event](https://openairdocs.org/ntsb-events/220) (defining event); cases with it: [Weatherly 620B, 4 cases](https://openairdocs.org/ntsb-events/220/sequence.md?model=9630605), [All aircraft, 780 cases](https://openairdocs.org/ntsb-events/220/sequence.md)
- [Maneuvering-low-alt flying: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Weatherly 620B, 9 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=9630605), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md)

## Analysis

The pilot reported that during an aerial application flight, he completed one pass over a field and initiated a climb to return for the second pass. As the climb progressed, he realized he did not have sufficient airspeed or altitude to maintain clearance from the approaching terrain. He was eventually able to complete the turn but did not have sufficient airspeed or altitude to avoid terrain and the airplane struck the ground. The airplane sustained substantial damage to both wings and the lower fuselage. The pilot reported no preimpact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation.

## Aircraft

- Registration: [N90393](https://openairdocs.org/aircraft/N90393), registered now, S/N 1594, built 1995 (OpenAirDocs)
- Reported make and model: WEATHERLY AVIATION CO INC 620B
- Registry model: [Weatherly 620B](https://openairdocs.org/model/weatherly-620b) (registry code 9630605) (OpenAirDocs)
- Registry engine: [Pratt & Whitney R-985 series](https://openairdocs.org/engine/pratt-whitney-r-985-series) (registry code 52008, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 1594
- Year built: 1995
- Airframe hours: 4915.3
- Engines: Pratt and Whitney 985 450 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Airworthiness certificate: Special, Restricted (Special)
- Last inspection: Annual, April 1, 2025, 37.5 hours before
- Destination: Same as departure
- Equipment: Unknown

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 27; injuries: none; commercial; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 2, without waivers/limitations; last flight review January 29, 2024; seat: right; restraint: 4-point; flight hours: 1,326.7 total, 249.7 in this make and model, 1,216.6 as pilot in command, 133 in the last 90 days, 45.5 in the last 30 days, 4.3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 160° at 9 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 77 °F, dew point 46 °F
- Altimeter: 29.88 inHg
- Observed at: K1NM, 4 nm away
- METAR: K1NM 300055Z AUTO 16009KT 10SM CLR 25/08 A2988 RMK AO2 SLP099 T02490079 $

## 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 20250529004899A](https://openairdocs.org/incident/20250529004899A), May 29, 2025: Weatherly Aviation Co Inc 620B, Lewistown, MT, Substantial damage. On may 29, 2025, at 1900 MDT a Weatherly 620B conducting an aerial application flight in Lewistown, MT suffered substantial damage. On may 30, 2025 at the…

## Docket (2 files)

The files NTSB released with the investigation on September 26, 2025, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=200245. 3.2 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 7 pages, 1.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19223988&FileExtension=pdf&FileName=r_NTSB-6120_Redacted-Rel.pdf
- Photos (item 2, PDF, 3 pages, 2 photos, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=19222989&FileExtension=pdf&FileName=Photos-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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