# STC SA4557NM

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Heavy Lift Helicopters Inc, United States
- Description: Installation of Retardant Tanks for the special purpose of Forest and Wildlife Conservation.  (Approved for SN 56-0530 only)
- Applied: February 15, 1989
- Status date: August 21, 2002
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A15NM](https://openairdocs.org/tcds/A15NM)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/A34C27C7CF403D9686256D47005601A2.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA4557NM

## ADs that name it (0)

None.

## Approved models (1)

- USDA Forest Service C-130A ([TCDS A15NM](https://openairdocs.org/tcds/A15NM))

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