Garmin 320 Installation Manual page 10

Antenna and cable installations on pressurized cabin aircraft require FAA approved installation design and
engineering substantiation data whenever such installations incorporate alteration (penetration) of the cabin
pressure vessel by connector holes and/or mounting arrangements.
For needed engineering support pertaining to the design and approval of such pressurized aircraft antenna
installations, it is recommended that the installer proceed according to any of the following listed alternatives:
1. Obtain approved antenna installation design data from the aircraft manufacturer.
2. Obtain an FAA approved Supplemental Type Certificate (STC) pertaining to and valid for the subject
antenna installation.
3. Contact the FAA Aircraft Certification Office in the appropriate Region and request identification of FAA
Designated Engineering Representatives (DERs) who are authorized to prepare and approve the required
antenna installation engineering data.
4. Obtain FAA Advisory Circular AC-183C and select (and contact) a DER from the roster of individuals
identified there under.
Contact an aviation industry organization such as the Aircraft Electronics Association and request their
assistance.
Page 6
Rev L
GTX 320/320A Installation Manual
190-00133-01