# N521AC: Sikorsky S-76A, registration cancelled 1983-12-14

- Type: Cancelled registration (FAA registry, deregistered aircraft)
- Cancelled: December 14, 1983
- Status when cancelled: Valid registration
- Airframe: [Sikorsky S-76A](https://openairdocs.org/model/sikorsky-s-76a) (registry code 8143006)
- Data sheets: [TCDS H1NE](https://openairdocs.org/tcds/H1NE) (OpenAirDocs)
- Serial number: 760159
- Type of aircraft: Rotorcraft
- Certificate issued: February 1, 1982
- Mode S code: A68CA8
- Owner when cancelled: [Amway Corp](https://openairdocs.org/faa-owner/AMWAY%20CORP)
- Location: [Ada, MI](https://openairdocs.org/faa-place/MI/Ada)
- Owner type: Corporation
- The mark today: https://openairdocs.org/aircraft/N521AC
- FAA registry: https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=521AC
- Page: https://openairdocs.org/deregistered/N521AC-1983-12-14

From the FAA registry file of November 3, 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 Sikorsky S-76A: https://openairdocs.org/model/sikorsky-s-76a.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 CHI83FA428](https://openairdocs.org/ntsb/CHI83FA428), Sep 14, 1983: Sikorsky S-76A (N521AC), Chicago, IL, destroyed

## 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 19830914048899A](https://openairdocs.org/incident/19830914048899A), Sep 14, 1983: Skrsky S76A (N521AC), Chicago, IL, Destroyed. Tail rotor cable routed over instead of under keeper, chafed, broke. Partial yaw control, ditched.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.