# STC ST121RM

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: Ports-of-Call Travel Club, United States
- Description: Installation of dual Marconi Omega navigation systems (Model CMA-740). (30A CV-990)
- Status date: June 25, 1981
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 4A30](https://openairdocs.org/tcds/4A30)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/562FDCF1743B08A885256CC300035F28.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/ST121RM

## ADs that name it (0)

None.

## Approved models (1)

- General Dynamics Corporation 30A ([TCDS 4A30](https://openairdocs.org/tcds/4A30))

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