# N1645: 2025 Cosmer Gary M S-21 OUTBOUND

- Status: Valid registration
- Airframe: [Cosmer Gary M S-21 OUTBOUND](https://openairdocs.org/model/cosmer-gary-m-s-21-outbound) (registry code 056429Q, 2 seats)
- Engine: [Rotax 915 IS series](https://openairdocs.org/engine/rotax-915-is-series) (registry code 55620)
- Data sheets: [TCDS E00051EN](https://openairdocs.org/tcds/E00051EN) (BRP-Rotax GmbH & Co KG) (OpenAirDocs)
- Serial number: 10230352
- Year built: 2025
- Type: Fixed wing single engine
- Engine type: Reciprocating
- Kit: Rans Designs Inc S-21 OUTBOUND
- Airworthiness: Experimental, amateur built
- Airworthiness date: June 5, 2026
- Certificate issued: July 9, 2025
- Expires: July 31, 2032
- Mode S code: A10391
- Registered owner: [Cosmer Gary M](https://openairdocs.org/faa-owner/COSMER%20GARY%20M)
- Location: [Oregon City, OR](https://openairdocs.org/faa-place/OR/Oregon%20City)
- Owner type: Individual
- Owner's area on the map: 45.3203° N, 122.5365° W: Placed by OpenAirDocs at the center of ZIP code 97045, 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=1645
- Page: https://openairdocs.org/aircraft/N1645

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 915 IS model are included.

## ADs that may apply (OpenAirDocs): 2 in force

### Matched by airframe (Cosmer Gary M S-21 OUTBOUND)

None in force.

### Matched by engine (Rotax 915 IS series)

- [AD 2026-04-02](https://openairdocs.org/ad/2026-04-02): Turbine Engine Reduction Gear · BRP-Rotax 915 iSc2 C24 and 915 iSc3 C24. Effective Mar 19, 2026
- [AD 2025-15-03](https://openairdocs.org/ad/2025-15-03): Reciprocating Engine Oil System · BRP-Rotax 912 iSc2 Sport, 912 iSc3 Sport, 915 iSc2 C24 and 1 more. Effective Aug 6, 2025

### Historical (superseded or no longer in force)

- [AD 2025-07-02](https://openairdocs.org/ad/2025-07-02) (historical): Reciprocating Engine Oil System · BRP-Rotax 912 iSc2 Sport, 912 iSc3 Sport, 915 iSc2 C24 and 1 more. Effective Apr 21, 2025

## Information bulletins (advisory)

None matched.

## NTSB investigations

None matched to N1645.

## FAA accident and incident reports

None matched to N1645.

## Reports on N1645 not matched to an aircraft (3)

They name N1645, but no registry record covers the date, the aircraft registered then was built later, or the report describes another aircraft.

- [Incident 19870207026819I](https://openairdocs.org/incident/19870207026819I), Feb 7, 1987: Boeing 727 (N1645), Boston, MA. Stabilizer became inoperative en route. Safe landing. Lubricated jack screw.
- [Incident 19830705061709I](https://openairdocs.org/incident/19830705061709I), Jul 5, 1983: Boeing 727295 (N1645), Charlotte, NC. Left main gear broke through blacktop during taxi. Passengers were removed. City dug gear out.
- [Incident 19810412024129I](https://openairdocs.org/incident/19810412024129I), Apr 12, 1981: Boeing 727295 (N1645), Jacksonville, FL. Made emergency descent and landing due to complete loss of pressurization control.

## 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 (Rotax 915 IS series)

- [STC SE01966WI](https://openairdocs.org/stc/SE01966WI): Use of GAMI G100UL High Octane Unleaded Avgas in spark ignition piston aircraft engines. General Aviation Modifications Inc. Lists 915 iSc2 C24

## Related

- Other Cosmer Gary M S-21 OUTBOUND aircraft: https://openairdocs.org/model/cosmer-gary-m-s-21-outbound/aircraft.md
- The Rotax 915 IS series engine: https://openairdocs.org/engine/rotax-915-is-series.md

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