# NTSB CHI88FA178: Sonerai IIL, N398, Oshkosh, WI, July 28, 1988

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Field investigation · Final report
- Date: July 28, 1988, 10:15 local (15:15 UTC)
- Place: Oshkosh, WI
- Location: 43.9844° N, 88.5570° W: Placed by OpenAirDocs at WITTMAN RGNL (OSH), within about a mile (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=43.9844&lon=-88.5570&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report November 28, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 13955
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CHI88FA178
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/13955/pdf
- Page: https://openairdocs.org/ntsb/CHI88FA178

## Sequence of events

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

- Loss of control - on ground/water, landing - flare/touchdown
  - weather condition - crosswind (contributing factor)
  - directional control - not maintained, pilot in command (cause)
  - ground loop/swerve - inadvertent, pilot in command (cause)
- On ground/water collision with object, landing - roll
  - object - runway light (contributing factor)

## Aircraft

- Registration: [N398](https://openairdocs.org/deregistered/N398-2013-02-27), registration cancelled 2013-02-27, S/N DWO893, built 1985 (OpenAirDocs)
- Reported make and model: SONERAI IIL
- Registry model: [Ouverson Dennis W SONERAI IIL](https://openairdocs.org/model/ouverson-dennis-w-sonerai-iil) (registry code 056595H) (OpenAirDocs)
- Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: DW0893
- Airframe hours: 110
- Engines: Volkswagen 1835 CC 60 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Ouverson, Dennis
- Airworthiness certificate: Special, Experimental (Special)
- Last inspection: Annual, August 12, 1987, 27 hours before
- Departed: CB5, BARABOO, WI
- Airport: OSH, Wittman Field, runway 36, 8,001 × 75 ft, concrete

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 41; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: rear; flight hours: 250 total, 110 in this make and model, 213 as pilot in command, 16 in the last 90 days, 5 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 260° at 12 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 90 °F, dew point 59 °F
- Altimeter: 30.00 inHg
- Observed at: OSH, 5 nm away

## 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 19880728035829A](https://openairdocs.org/incident/19880728035829A), Jul 28, 1988: Amtrmo SONERAI2, Oshkosh, WI, Substantial damage. Lost control landing on crosswind runway. Collapsed gear. Did not question runway assignment.

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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