# NTSB WPR20CA151: Let L 33 Solo, N355BA, Arlington, WA, May 11, 2020

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Class 4 · Data collection · Final report
- Date: May 11, 2020, 12:53 local (19:53 UTC)
- Place: Arlington, WA
- Coordinates: 48.160831, -122.158889 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=48.1608&lon=-122.1589&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Defining event: [Landing: Loss of lift](https://openairdocs.org/ntsb-events/500)
- Highest injury: No injuries
- Injuries: 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): 101295
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR20CA151
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101295/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=101295
- Page: https://openairdocs.org/ntsb/WPR20CA151

## Probable cause

The loss of lift while on final approach which resulted in a hard off-airport landing.

## Findings

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

- [Temp/humidity/pressure: thermal lifting](https://openairdocs.org/ntsb-findings/03031040): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Let L 33 SOLO, 1 case](https://openairdocs.org/ntsb-findings/03031040/cases.md?model=1360309), [All aircraft, 53 cases](https://openairdocs.org/ntsb-findings/03031040/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: [Let L 33 SOLO, 2 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=1360309), [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.

- [Landing: Loss of lift](https://openairdocs.org/ntsb-events/500) (defining event); cases with it: [Let L 33 SOLO, 3 cases](https://openairdocs.org/ntsb-events/500/sequence.md?model=1360309), [All aircraft, 252 cases](https://openairdocs.org/ntsb-events/500/sequence.md)
- [Landing-flare/touchdown: Hard landing](https://openairdocs.org/ntsb-events/092); cases with it: [Let L 33 SOLO, 2 cases](https://openairdocs.org/ntsb-events/092/sequence.md?model=1360309), [All aircraft, 2,102 cases](https://openairdocs.org/ntsb-events/092/sequence.md)
- [Landing-landing roll: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Let L 33 SOLO, 5 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=1360309), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md)

## Analysis

The glider pilot reported that while on final approach to land, the ground speed decreased and the glider descended faster than expected. Unable to reach the runway, he diverted to a gravel area to land out. The glider landed hard, and during the landing roll he heard a loud bang that was later identified as a pothole. The glider sustained substantial damage to the fuselage. The pilot reported no mechanical malfunctions with the glider that would have precluded normal operation.

## Aircraft

- Registration: [N355BA](https://openairdocs.org/deregistered/N355BA-2023-03-03), registration cancelled 2023-03-03, S/N 990506, built 1999 (OpenAirDocs)
- Reported make and model: Let L 33 SOLO (No Series)
- Registry model: [Let L 33 SOLO](https://openairdocs.org/model/let-l-33-solo) (registry code 1360309) (OpenAirDocs)
- Registry engine: [NONE](https://openairdocs.org/engine/none) (registry code 00000, none) (OpenAirDocs)
- Category: Glider
- Serial number: 990506
- Year built: 1999
- Airframe hours: 814.35
- Damage: Substantial damage
- Flight: Personal, Part 91
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, May 8, 2020
- Departed: AWO, Arlington, WA
- Destination: AWO, Arlington, WA
- Airport: AWO, Arlington Muni, runway 34, 5,332 × 100 ft, asphalt
- Equipment: None

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 58; injuries: none; student, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: basicmed, without waivers/limitations; seat: center; restraint: 4-point; flight hours: 4,561 total, 4 in this make and model, 15 in the last 90 days, 7 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 350° at 5 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 75 °F, dew point 46 °F
- Altimeter: 30.01 inHg
- Observed at: KPAE, 16 nm away

## Docket (3 files)

The files NTSB released with the investigation on October 9, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=101295. 7.8 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 5.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=10078717&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf
- Pilot's statement (item 2, PDF, 4 pages, 329 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=10078787&FileExtension=pdf&FileName=355BA%20NTSB%20Flight%20Report_Redacted-Rel.pdf
- Photos (FAA) (item 3, PDF, 4 pages, 1.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=10078823&FileExtension=pdf&FileName=Photographs%20(FAA)-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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