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Atlas / STC / SA1-427

FAA · Supplemental Type Certificate

STC SA1-427

Pratt & Whitney R-985 engine installation with Simmonds Aero- cessories 580047 fuel injector per STC SE1-391, and takeoff weight increase to 9,800 lbs. and landing weight to 9,400 lbs. per STC SA2-820.

Current Reissued Aircraft Small Multi-Engine Rev 10/06/2006 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
  • § 21.47

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