# N85BU: 1940 Dornier BU 133

- Status: Valid registration
- Airframe: [Dornier BU 133](https://openairdocs.org/model/dornier-bu-133) (registry code 2999006, 2 seats)
- Engine: [Siemens SH14](https://openairdocs.org/engine/siemens-sh14) (registry code 57001)
- Data sheets: [TCDS Group 3 Siemens Halske](https://openairdocs.org/tcds/Group%203%20Siemens%20Halske) (Siemens Halske) (OpenAirDocs)
- Serial number: 32
- Year built: 1940
- Type: Fixed wing single engine
- Engine type: Reciprocating
- Airworthiness: Experimental, exhibition
- Airworthiness date: January 11, 2002
- Certificate issued: February 18, 2020
- Expires: February 28, 2030
- Mode S code: ABA52B
- Registered owner: [Martin James D](https://openairdocs.org/faa-owner/MARTIN%20JAMES%20D)
- Location: [Graford, TX](https://openairdocs.org/faa-place/TX/Graford)
- Owner type: Individual
- Owner's area on the map: 32.9010° N, 98.3163° W: Placed by OpenAirDocs at the center of ZIP code 76449, 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=85BU
- Page: https://openairdocs.org/aircraft/N85BU

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 (Dornier BU 133)

None in force.

### Matched by engine (Siemens SH14)

None in force.

## Information bulletins (advisory)

None matched.

## NTSB investigations

None matched to N85BU.

## FAA accident and incident reports

None matched to N85BU.

## 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) (1)

Approved for this aircraft's airframe or engine model, in force first, then newest. The registry doesn't record which STCs an aircraft has; its records do.

### Approved for the engine (Siemens SH14)

- [STC SE04651CH](https://openairdocs.org/stc/SE04651CH): To allow use of l00R grade aviation fuel meeting Swift Fuel, LLC specification SPEC-l00R-22. Swift Fuels LLC

## Related

- Other Dornier BU 133 aircraft: https://openairdocs.org/model/dornier-bu-133/aircraft.md
- The Siemens SH14 engine: https://openairdocs.org/engine/siemens-sh14.md

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