# NTSB WPR26LA203: Pzl-Swidnik PW-5, N157AJ, Soap Lake, WA, May 23, 2026

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Class 4 · Limited · Final report
- Date: May 23, 2026, 14:25 local (21:25 UTC)
- Place: Soap Lake, WA
- Coordinates: 47.3884, -119.52208 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.3884&lon=-119.5221&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Defining event: [Enroute: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report August 27, 2026
- 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): 203101
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR26LA203
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/203101/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=203101
- Page: https://openairdocs.org/ntsb/WPR26LA203

## Probable cause

The pilot’s failure to ensure the proper preflight assembly of the glider's wing attachment system, which resulted in substantial damage to the wing structure during flight.

## Findings

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

- [Inspection: preflight inspection](https://openairdocs.org/ntsb-findings/02061510): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Pzl-Swidnik PW-5, 1 case](https://openairdocs.org/ntsb-findings/02061510/cases.md?model=9810150), [All aircraft, 551 cases](https://openairdocs.org/ntsb-findings/02061510/cases.md)
- [Inspection: preflight inspection](https://openairdocs.org/ntsb-findings/02061510): Personnel issues › Task performance · Ground crew (probable cause); cases with it: [Pzl-Swidnik PW-5, 1 case](https://openairdocs.org/ntsb-findings/02061510/cases.md?model=9810150), [All aircraft, 551 cases](https://openairdocs.org/ntsb-findings/02061510/cases.md)
- [Wing structure: attach fittings (on wing)](https://openairdocs.org/ntsb-findings/01035740): Aircraft › Aircraft structures · Incorrect use/operation (probable cause); cases with it: [Pzl-Swidnik PW-5, 1 case](https://openairdocs.org/ntsb-findings/01035740/cases.md?model=9810150), [All aircraft, 21 cases](https://openairdocs.org/ntsb-findings/01035740/cases.md)
- [Wing structure: fus (attach fitting on wing)](https://openairdocs.org/ntsb-findings/01035741): Aircraft › Aircraft structures · Not inspected (probable cause); cases with it: [Pzl-Swidnik PW-5, 1 case](https://openairdocs.org/ntsb-findings/01035741/cases.md?model=9810150), [All aircraft, 3 cases](https://openairdocs.org/ntsb-findings/01035741/cases.md)

## Sequence of events

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

- [Enroute: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [Pzl-Swidnik PW-5, 1 case](https://openairdocs.org/ntsb-events/330/sequence.md?model=9810150), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md)
- [Enroute: Aircraft structural failure](https://openairdocs.org/ntsb-events/337); cases with it: [Pzl-Swidnik PW-5, 1 case](https://openairdocs.org/ntsb-events/337/sequence.md?model=9810150), [All aircraft, 290 cases](https://openairdocs.org/ntsb-events/337/sequence.md)

## Analysis

The pilot reported that he and three club members assembled the glider before the accidewnt flight, following the manufacturer's assembly procedures. After a preflight inspection and positive control check, the glider was towed and released. Approximately 10 minutes later, the pilot heard a sharp cracking sound and elected to return to the airport and land. A postflight examination revealed substantial damage to the wing spar root, wing, and fuselage. During disassembly of the glider following the accident, the assembly crew noted that the right main wing pin was in its halfway position and had not been secured. The left main wing pin was fully inserted and secured. They noted that the in-flight structural damage was likely due to the right main wing pin not being fully seated and secured during assembly.

## Aircraft

- Registration: [N157AJ](https://openairdocs.org/aircraft/N157AJ), registered now, S/N 17.10.018, built 1998 (OpenAirDocs)
- Reported make and model: PZL-SWIDNIK PW-5
- Registry model: [Pzl-Swidnik PW-5](https://openairdocs.org/model/pzl-swidnik-pw-5) (registry code 9810150) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Glider
- Serial number: 17.10.018
- Year built: 1998
- Airframe hours: 951.2
- Damage: Substantial damage
- Flight: Personal, Part 91
- Operator: Puget Sound Soaring Association
- Registered owner: Puget Sound Soaring Association
- Airworthiness certificate: Standard, Utility
- Last inspection: Annual, February 7, 2026
- Departed: KEPH, Ephrata, WA
- Airport: None, In flight about 5.5 mile north of EPH
- Equipment: None

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 42; injuries: none; private; last flight review May 12, 2026; seat: single; restraint: 4-point; flight hours: 48 total, 18 in this make and model, 24 as pilot in command, 3 in the last 90 days, 3 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 220° at 10 knots, gusting 19
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 82 °F, dew point 37 °F
- Altimeter: 29.77 inHg
- Turbulence: Light
- Observed at: EPH, 5 nm away
- METAR: METAR KEPH 232053Z AUTO 22010G19KT 10SM CLR 28/03 A2977 RMK AO2 SLP075 T02830033 58006=

## 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 20260523008239A](https://openairdocs.org/incident/20260523008239A), May 23, 2026: Pzl-Swidnik PW-5, Ephrata, WA, Substantial damage. Airman pablo a. aguilar vergara acted as pilot in command (PIC) of aircraft [privacy data omitted] near Ephrata Municipal Airport (keph), Ephrata, Washington,…

## Docket (2 files)

The files NTSB released with the investigation on August 27, 2026, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=203101. 4.7 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 10 pages, 4.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=20489143&FileExtension=pdf&FileName=WPR26LA203%206120.1%20Redacted-Rel.pdf
- Photos (item 2, PDF, 4 pages, 435 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=20488528&FileExtension=pdf&FileName=Photographs-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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