FAA · Supplemental Type Certificate
STC ST11861AT
Installation of a new Control Wheel Push-to-Talk (PTT) switch with three positions and latchable in accordance with the MDL shown in the attached AML No. ST11861AT.
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 (7)
Certification basis — 14 CFR
The STC PDF on drs.faa.gov is the authoritative document — it lists installation instructions, ICA requirements, and any limitations. Open PDF ↗