# N21: not currently registered

- Registered now: No (not in the FAA registry file). The mark may be reserved or free to assign
- Earlier aircraft: 2
- Last cancelled: March 12, 1947
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=21
- Page: https://openairdocs.org/aircraft/N21

## Aircraft that carried N21

- [Cancelled 1947-03-12](https://openairdocs.org/deregistered/N21-1947-03-12): Fairchild 24 G, S/N 2924, built 1937. Owner: [Civil Aeronautics Authority](https://openairdocs.org/faa-owner/CIVIL%20AERONAUTICS%20AUTHORITY), [Washington, DC](https://openairdocs.org/faa-place/DC/Washington)
- [Cancelled 1931-03-10](https://openairdocs.org/deregistered/N21-1931-03-10): Boeing 100, S/N 1142, built 1929. Owner: [U S Dept Of Commerce](https://openairdocs.org/faa-owner/U%20S%20DEPT%20OF%20COMMERCE), [Washington, DC](https://openairdocs.org/faa-place/DC/Washington)

## NTSB investigations on N21 (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 FTW04IA078](https://openairdocs.org/ntsb/FTW04IA078), Feb 19, 2004: Beech C90 (N21), Oklahoma City, OK, incident, minor damage. Probable cause: The failure of the right main landing gear to extend due to an improperly installed attachment bolt by other maintenance personnel.

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