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Atlas / STC / SH2389NM

FAA · Supplemental Type Certificate

STC SH2389NM

Installation of an Electronics International Digital Temperature Indicator with related thermocouples, adapters and harness to monitor the temperature fo the main gear box bearings.

Current Issued Aircraft Rev 11/10/1983 View PDF on drs.faa.gov ↗

What is an STC?

A Supplemental Type Certificate authorizes a major modification or alteration to an FAA-certificated aircraft. STCs are how operators legally install new avionics, change fuel systems, add floats, swap engines, etc. — every change beyond a minor modification needs one.

Certification basis — 14 CFR

Specific sections

  • Sec. 111
  • Sec. 113
  • Sec. 115
  • Sec. 117
  • Sec. 119
  • Sec. 120

The STC PDF on drs.faa.gov is the authoritative document — it lists installation instructions, ICA requirements, and any limitations. Open PDF ↗