# N421SY: 1975 Cessna 421C, registration cancelled 2014-04-18

- Type: Cancelled registration (FAA registry, deregistered aircraft)
- Cancelled: April 18, 2014
- Status when cancelled: Second renewal notice
- Airframe: [Cessna 421C](https://openairdocs.org/model/cessna-421c) (registry code 2076016)
- Data sheets: [TCDS A7CE](https://openairdocs.org/tcds/A7CE) (OpenAirDocs)
- Serial number: 421C0051
- Year built: 1975
- Type of aircraft: Fixed wing multi engine
- Airworthiness: Standard, normal
- Airworthiness date: February 23, 1976
- Certificate issued: April 9, 2009
- Last registry action: May 11, 2011
- Mode S code: A500FD
- Owner when cancelled: [S & S Aviation LLC](https://openairdocs.org/faa-owner/S%20%26%20S%20AVIATION%20LLC)
- Location: [Ipswich, SD](https://openairdocs.org/faa-place/SD/Ipswich)
- Owner type: Corporation
- Owner's area on the map: 45.4378° N, 98.9365° W: Placed by OpenAirDocs at the center of ZIP code 57451, within about 12 miles (OpenAirDocs). The owner's mailing address, not where the aircraft was based
- The mark today: https://openairdocs.org/aircraft/N421SY
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=421SY
- Page: https://openairdocs.org/deregistered/N421SY-2014-04-18

From the FAA registry file of October 29, 2026, cancelled registrations. Owners' street addresses are left out. The Mode S code belongs to the N-number, not the airframe.

ADs and bulletins for the Cessna 421C: https://openairdocs.org/model/cessna-421c.md

## 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 CEN12FA100](https://openairdocs.org/ntsb/CEN12FA100), Dec 9, 2011: Cessna 421C (N421SY), Sioux Falls, SD, substantial damage, 4 fatal. Probable cause: The pilot’s failure to maintain adequate airspeed after shutting down one engine, which resulted in an inadvertent aerodynamic stall and impact with terrain. Contributing to the accident was the…

## 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 20111209029109A](https://openairdocs.org/incident/20111209029109A), Dec 9, 2011: Cessna 421C (N421SY), Sioux Falls, SD, Destroyed, 4 fatal. On December 9th, 2011 at 1422 CST, a Cessna 421C aircraft N421SY operated by quest aviation and piloted by [privacy data omitted], took off from Joe Foss Field…

## Other aircraft with N421SY

- [Registered now](https://openairdocs.org/aircraft/N421SY): Textron 208B, S/N 208B5636, built 2021

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