# N121SD: Monnett SONERAI-IIB

- Status: Valid registration
- Airframe: [Monnett SONERAI-IIB](https://openairdocs.org/model/monnett-sonerai-iib) (registry code 0565935, 2 seats)
- Engine: [Volkswagen CONVERSION](https://openairdocs.org/engine/volkswagen-conversion) (registry code 63501)
- Serial number: 2-2B
- Type: Fixed wing single engine
- Engine type: Reciprocating
- Airworthiness: Experimental, amateur built
- Airworthiness date: February 26, 1980
- Certificate issued: May 29, 2026
- Expires: May 31, 2033
- Mode S code: A058FD
- Registered owner: [Doiron Stephen R](https://openairdocs.org/faa-owner/DOIRON%20STEPHEN%20R)
- Location: [New Braunfels, TX](https://openairdocs.org/faa-place/TX/New%20Braunfels)
- Owner type: Individual
- Owner's area on the map: 29.7588° N, 98.1911° W: Placed by OpenAirDocs at the center of ZIP code 78132, within about 8 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=121SD
- Page: https://openairdocs.org/aircraft/N121SD

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.

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

### Matched by airframe (Monnett SONERAI-IIB)

None in force.

### Matched by engine (Volkswagen CONVERSION)

None in force.

## Information bulletins (advisory)

None matched.

## NTSB investigations

None matched to N121SD.

## FAA accident and incident reports

None matched to N121SD.

## 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.

## Earlier aircraft with N121SD

The FAA can reassign an N-number once a registration is cancelled. These aircraft carried N121SD before.

- [Cancelled 2018-01-11](https://openairdocs.org/deregistered/N121SD-2018-01-11): Sawyer Steve M GOLDWING, S/N 121, built 1988. Registration expired, pending cancellation. Owner: [Sawyer Steve M](https://openairdocs.org/faa-owner/SAWYER%20STEVE%20M), [Lincoln, CA](https://openairdocs.org/faa-place/CA/Lincoln)

## Related

- Other Monnett SONERAI-IIB aircraft: https://openairdocs.org/model/monnett-sonerai-iib/aircraft.md
- The Volkswagen CONVERSION engine: https://openairdocs.org/engine/volkswagen-conversion.md

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