# N121YT: 2008 Flight Design CTLS

- Status: Valid registration
- Airframe: [Flight Design CTLS](https://openairdocs.org/model/flight-design-ctls) (registry code 060005B, 2 seats)
- Engine: [Rotax 912ULS series](https://openairdocs.org/engine/rotax-912uls-series) (registry code 55572)
- Serial number: 08-04-10
- Year built: 2008
- Type: Fixed wing single engine
- Engine type: 4 cycle
- Airworthiness: Experimental, operating light-sport, previously under 21.190
- Airworthiness date: August 6, 2024
- Certificate issued: January 25, 2024
- Expires: January 31, 2031
- Mode S code: A059A1
- Registered owner: [Smith Kenneth S](https://openairdocs.org/faa-owner/SMITH%20KENNETH%20S)
- Location: [Fish Creek, WI](https://openairdocs.org/faa-place/WI/Fish%20Creek)
- Owner type: Individual
- Owner's area on the map: 45.1098° N, 87.2090° W: Placed by OpenAirDocs at the center of ZIP code 54212, within about 3 miles (OpenAirDocs). The owner's mailing address, not where the aircraft is based
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=121YT
- Page: https://openairdocs.org/aircraft/N121YT

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 Rotax 912ULS model are included.

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

### Matched by airframe (Flight Design CTLS)

None in force.

### Matched by engine (Rotax 912ULS series)

None in force.

## Information bulletins (advisory)

None matched.

## NTSB investigations (1)

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.

- [NTSB ERA22LA011](https://openairdocs.org/ntsb/ERA22LA011), Oct 10, 2021: Flight Design Ctls (N121YT), Greenville, SC, substantial damage. Probable cause: A total loss of engine power resulting from the in-flight disconnection of oil hoses from the oil thermostat.

## FAA accident and incident reports (1)

From the FAA Accident/Incident Data System. Reports are matched to registry aircraft by N-number and event date, checked against the reported make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model.

- [Accident 20211010018819A](https://openairdocs.org/incident/20211010018819A), Oct 10, 2021: Flight Design Gmbh CTLS (N121YT), Greenville, SC, Substantial damage. The aircraft was at 5500 feet in level Flight when the oil pressure dropped quickly. He declared and turned toward the airport. The engine seized up before…

## 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 Flight Design CTLS aircraft: https://openairdocs.org/model/flight-design-ctls/aircraft.md
- The Rotax 912ULS series engine: https://openairdocs.org/engine/rotax-912uls-series.md

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