# NTSB SEA88LA115: Peterson J-4, Ephrata, WA, June 20, 1988

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Limited investigation · Final report
- Date: June 20, 1988, 13:00 local (20:00 UTC)
- Place: Ephrata, WA
- Coordinates: 47.269989, -119.590423 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.2700&lon=-119.5904&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed, report August 8, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 40834
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA88LA115
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40834/pdf
- Page: https://openairdocs.org/ntsb/SEA88LA115

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- In flight encounter with weather, maneuvering
  - weather condition - downdraft (contributing factor)
  - weather evaluation - misjudged, pilot in command (cause)
- Forced landing, descent - emergency
- Dragged wing,rotor,pod,float or tail/skid, landing - flare/touchdown
  - terrain condition - none suitable (contributing factor)
  - terrain condition - rough/uneven (contributing factor)
  - ground loop/swerve

## Analysis

THE GLIDER PLT WAS MANEUVERING FOR A THERMAL WHEN HE ENCOUNTERED A DOWNDRAFT. THE PLT SAID INSUFFICIENT ALTITUDE REMAINED FOR AN AIRPORT LANDING. AN OFF-AIRPORT LANDING ON ROUGH TERRAIN RESULTED IN DAMAGE TO THE GLIDER.

## Aircraft

- Registration: CGHGZ (not matched to a registry record)
- Reported make and model: PETERSON J-4
- Category: Glider
- Serial number: 7
- Airframe hours: 64
- Engines: unknown
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Bryan M. Swansburg
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, August 14, 1987, 8 hours before

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 22; commercial; airplane ratings: single-engine land; medical: class 1, valid medical--w/ waivers/lim; seat: center; flight hours: 284 total, 5 in this make and model, 203 as pilot in command, 22 in the last 90 days, 12 in the last 30 days, 2 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 230° at 15 knots
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 88 °F, dew point 36 °F
- Altimeter: 29.00 inHg
- Observed at: EPH, 5 nm away

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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