This advisory circular (AC) provides guidance on airworthiness approval for designers, manufacturers, and installers of Satellite Voice (SATVOICE) equipment supporting air traffic service (ATS). In this AC, the Federal Aviation Administration (FAA) recommends one way to gain airworthiness approval for SATVOICE equipment. This AC is not mandatory and does not constitute a regulation. This AC describes an acceptable means, but not the only means, to gain airworthiness approval for your SATVOICE equipment. However, if you use the means described in this AC, you must follow it in its entirety.