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Atlas / STC / SH4393NM

FAA · Supplemental Type Certificate

STC SH4393NM

Installation of aft transmission housing, P/N A07D2231-15, modified to accept the Verto l107-II helicopter aft transmission accessory gears and modified cover, P/N A02D2240.

Current Amended Aircraft Rotorcraft Rev 06/05/2007 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.

Applicable aircraft (3)

Certification basis — 14 CFR

Specific sections

  • Sec. 111
  • Sec. 113
  • Sec. 115
  • Sec. 117
  • Sec. 119
  • Sec. 120
  • § 21.47

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