Garmin GTX 320/320A TRANSPONDER INSTALLATION MANUAL
Brand: Garmin, Pages: 37
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GTX 320/320A Installation Manual Page 17
A.1 Continued Airworthiness
Other than for regulatory periodic functional checks, maintenance of the GTX 320/320A is “on condition” only.
Refer to the GTX 320 and GTX 320A Maintenance Manuals. Periodic maintenance of the GTX 320/320A is not
This section provides assistance to the installing agency in preparing Instructions for Continued Airworthiness
(ICA) in response to Bulletin Number HBAW 98-18, “Checklist for Instructions for Continued Airworthiness for
Major Alterations Approved Under the Field Approval Process”, effective 10/7/98.
Aviation Authority approved installers are hereby granted permission to reference appropriate service
instructions and excerpts from this Installation Manual to accomplish the Instructions for Continued
Airworthiness. This permission does not construe suitability of the documents. It is the applicant’s
responsibility to determine the suitability of the documents for the ICA.
Following is a suggested ICA for a GARMIN GTX 320/320A unit installation. Some of the checklist items do
not apply, in which case they should be marked “N/A” (Not Applicable).
INSTRUCTIONS FOR CONTINUED AIRWORTHINESS, GARMIN GTX 320/320A
[Aircraft that has been altered: Registration (N-) number, Make, Model and Serial Number]
Purpose and Arrangement: This document identifies the Instructions for Continued Airworthiness for the
modification of the above aircraft by installation of a GARMIN GTX 320/320A.
Applicability: Applies to aircraft altered by installation of the GARMIN GTX 320/320A.
Definitions/Abbreviations: None, N/A.
Precautions: None, N/A.
Units of Measurement: None, N/A.
Referenced Publications: GARMIN GTX 320/320A Installation Manual, P/N 190-00133-01
GARMIN GTX 320 Maintenance Manual, P/N 190-00133-02
GARMIN GTX 320A Maintenance Manual, P/N 190-00133-08
GARMIN STC # [applicable STC number for the specific model installed, refer
to Appendix B of this manual].
GARMIN GTX 320/320A Pilot’s Guide, P/N 190-00133-09.
Distribution: This document should be a permanent aircraft record.
2. Description of the Alteration
Installation of the GARMIN GTX 320/320A, with interface to Encoding Altimeter or Blind Encoder. Refer
to section 2.4 and Appendix B of this manual for interconnect information. Antenna installation, removal
and replacement should be in accordance with applicable provisions of AC43.13-1B and 43.13-2A.
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Page 18 GTX 320/320A Installation Manual
3. Control, Operation Information
Refer to the GTX 320/320A Pilot’s Guide.
4. Servicing Information
5. Maintenance Instructions
Maintenance of the GTX 320/320A is ‘on condition’ only. Periodic maintenance is not required. Refer to
the GTX 320 and the 320A Series Maintenance Manuals.
6. Troubleshooting Information
Refer to the GTX 320 and the GTX 320A Maintenance Manuals.
7. Removal and Replacement Information
Refer to section 2.4 of this manual. If the unit is removed and reinstalled, a functional check of the
equipment should be conducted in accordance with section 3.2 of this manual.
Refer to Appendix B of this manual.
9. Special Inspection Requirements
Application of Protective Treatments
11. Data: Relative to Structural Fasteners
Antenna installation, removal and replacement should be in accordance with applicable provisions of
AC43.13-1A and 43.13-2A. Also, refer to section 2.3 of this manual.
12. Special Tools
This Section is for Commuter Category Aircraft Only
A. Electrical loads: Refer to section 1.3 of this manual.
B. Methods of balancing flight controls: N/A.
C. Identification of primary and secondary structures: N/A.
D. Special repair methods applicable to the airplane: Antenna installation, removal, and replacement should
be in accordance with applicable provisions of AC43.13-1B and 43.13-2A.
14. Overhaul Period
No additional overhaul time limitations.
15. Airworthiness Limitation Section
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GTX 320/320A Installation Manual Page 19
To revise this ICA, a letter must be submitted to the local FSDO with a copy of the revised FAA Form 337,
and revised ICA. The FAA inspector accepts the change by signing Block 3 and including the following
“The attached revised/new Instructions for Continued Airworthiness (date ______) for the above aircraft or
component major alteration have been accepted by the FAA, superseding the Instructions for Continued
Airworthiness (date ______).”
Flight Standards Inspectors have the resources to respond to questions regarding the ICA.
Implementation and Record Keeping
For major alterations performed in accordance with FAA field approval policy, the owner/operator operating
under Part 91 is responsible for ensuring that the ICA is made part of the applicable section 91.409 inspection
program for their aircraft. This is accomplished when a maintenance entry is made in the aircraft’s maintenance
record in accordance with section 43.9. This entry records the major alteration and identifies the original ICA
location (e.g., Block 8 of FAA Form 337, dated ______) along with a statement that the ICA is now part of the
aircraft’s inspection/maintenance requirements.
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Page 20 GTX 320/320A Installation Manual
A.2 ENVIRONMENTAL QUALIFICATION FORM
NOMENCLATURE: GTX 320 Airborne ATC Transponder Equipment
TYPE/MODEL/PART NO.: 010-00135-00/10 TSO - C74c Class 1A
MANUFACTURER'S SPECIFICATION AND/OR OTHER APPLICABLE SPECIFICATION: 004-00042-00
MANUFACTURER: GARMIN INTERNATIONAL
ADDRESS: 1200 E 151st St, Olathe, KANSAS 66062
Conditions RTCA DO-160C
SectionDescription of Conducted Tests
Temperature and Altitude 4.0 Equipment tested to Categories A1 & D1 except
Low Temperature 4.5.1
High Temperature 4.5.2. & 4.5.3
In-Flight Loss of Cooling 4.5.4 Cooling air not required
Temperature Variation 5.0 Equipment tested to Category C
Humidity 6.0 Equipment tested to Category A
Shock 7.0 Equipment tested according to DO-160C, Par.
Crash Safety 7.3
Vibration 8.0 Equipment tested without shock mounts to
Categories B, M and N (Table 8-1)
Explosion 9.0 Equipment identified as Category X, no test
Waterproofness 10.0 Equipment identified as Category X, no test
Fluids Susceptibility 11.0 Equipment identified as Category X, no test
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GTX 320/320A Installation Manual Page 21
Conditions RTCA DO-160C
SectionDescription of Conducted Tests
Sand and Dust 12.0 Equipment identified as Category X, no test
Fungus 13.0 Equipment identified as Category X, no test
Salt Spray 14.0 Equipment identified as Category X, no test
Magnetic Effect 15.0 Equipment tested to Class Z
Power Input 16.0 Equipment tested to Category B
Voltage Spike 17.0 Equipment tested to Category A
Susceptibility18.0 Equipment tested to Category B
Susceptibility19.0 Equipment tested to Category A
Susceptibility20.0 Equipment tested to Category U
Radio Frequency Emission 21.0 Equipment tested to Category Z
Lightning Induce Transient
Susceptibility22.0 Equipment identified as Category XXXX, no test
Lightning Direct Effects 23.0 Equipment identified as Category X, no test
Icing 24.0 Equipment identified as Category X, no test