# N25531: 1940 Rearwin 8135

- Status: Valid registration
- Airframe: [Rearwin 8135](https://openairdocs.org/model/rearwin-8135) (registry code 7070304, 2 seats)
- Engine: [Ken Royce 7 series](https://openairdocs.org/engine/ken-royce-7-series) (registry code 37001)
- Serial number: 818
- Year built: 1940
- Type: Fixed wing single engine
- Engine type: Reciprocating
- Airworthiness: Standard
- Airworthiness date: October 30, 1955
- Certificate issued: January 29, 2003
- Expires: April 30, 2029
- Mode S code: A26CEC
- Registered owner: [Mertesdorf John](https://openairdocs.org/faa-owner/MERTESDORF%20JOHN)
- Location: [Nicollet, MN](https://openairdocs.org/faa-place/MN/Nicollet)
- Owner type: Individual
- Owner's area on the map: 44.3269° N, 94.1969° W: Placed by OpenAirDocs at the center of ZIP code 56074, within about 5 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=25531
- Page: https://openairdocs.org/aircraft/N25531

From the FAA registry file of October 24, 2026. ADs below are matched by the registry's airframe and engine model codes. They may apply; each AD's applicability can narrow it by serial number, part number or installed equipment. This is not a compliance determination. The registry lists only the engine series, so ADs for every Ken Royce 7 model are included.

## ADs that may apply (OpenAirDocs): 0 in force

### Matched by airframe (Rearwin 8135)

None in force.

### Matched by engine (Ken Royce 7 series)

None in force.

## Information bulletins (advisory)

None matched.

## NTSB investigations

None matched to N25531.

## FAA accident and incident reports

None matched to N25531.

## Service difficulty reports

None filed for this aircraft. Matched to this aircraft by N-number and event date, checked against the reported serial number, make and model.

## STCs that may be installed (OpenAirDocs)

None matched to this aircraft's models.

## Related

- Other Rearwin 8135 aircraft: https://openairdocs.org/model/rearwin-8135/aircraft.md
- The Ken Royce 7 series engine: https://openairdocs.org/engine/ken-royce-7-series.md

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