Garmin GTX 335 w GPS Installation Guidance page 23

2.2.2 Preservation of Certified Systems
It is the responsibility of the installer using the data provided in this STC to preserve the essential
characteristics of the aircraft in accordance with the aircraft manufacturer's original design and the
requirements of 14 CFR Part 23.
2.2.3 Major Alterations
The installation of the GTX 335 system is a major alteration to the aircraft type design. After a major
alteration, the aircraft must be returned to service in a procedure satisfactory to the applicable aviation
authority. An example would be a completed FAA Form 337 submitted to the applicable FAA office. This
form must have the major alteration to include the equipment and systems the GTX is interfaced to.
2.2.4 Antennas
The GTX 335 units can only use transponder and SBAS/GPS antennas that comply with the requirements
as specified in section 3. Installation of antennas are not provided in this STC and separate approval is
necessary. Antennas, cables, and wiring interfaced to the GTX transponder system must not be installed in
fuel bays.
2.2.5 Pressurized Aircraft
Changes to the pressure vessel are not part of the GTX 33/330 and GTX 3X5 Part 23 AML STC. More data
from the aircraft manufacturer or other FAA approved data is necessary.
190-00734-17
Rev. 1
GTX 335 w/GPS Installation Guidance
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