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G5 STC SA01818WI: What the Approval Covers
The G5’s STC is more than a statement that the instrument is “approved.” The aircraft model, installation configuration, interfaces and supporting documents all matter.
What Is Garmin G5 STC SA01818WI?
SA01818WI is Garmin’s FAA Supplemental Type Certificate for the installation of the G5 Electronic Flight Instrument in aircraft covered by its Approved Model List. The FAA Dynamic Regulatory System identifies Garmin International Inc. as the STC holder and describes the type-design change as installation of the Garmin G5 Electronic Flight Instrument.
The key phrase is Approved Model List. The approval is not a universal authorization for installing a G5 in any aircraft. The applicable aircraft model and configuration must fall within the approved data.
The three questions that matter
- Is the aircraft on the applicable AML?
- Is the proposed G5 installation configuration covered?
- Are the required installation documents and interfaces being followed?
What Does the G5 STC Actually Approve?
Garmin’s current G5 Part 23 AML STC Installation Manual says it applies to modification of an aircraft listed on SA01818WI and that only the interfaces between the G5 and equipment listed in the manual are approved by the STC.
| STC question | What to verify |
|---|---|
| Aircraft eligibility | The aircraft make/model and applicable configuration are covered by the AML. |
| G5 function | Whether the proposed installation is for the approved G5 attitude, DG or HSI application. |
| Interfaces | The connected equipment and interface are among those covered by the approved installation data. |
| Installation data | The current applicable Garmin installation documentation and STC permission are used. |
| Aircraft limitations | Any limitations and retained instruments required by the STC are satisfied. |
Why the AML Matters More Than the G5 Product Page
A product page can describe what the G5 does. The AML and installation data answer a different question: where and how the equipment can be installed under the approved design change.
That distinction is especially important when an aircraft owner sees a G5 installation in another aircraft and assumes the same configuration is automatically available for their airplane.
G5 Attitude, DG and HSI Installations Are Not Identical
The G5 can be installed in different approved roles. Garmin’s STC documentation covers G5 attitude and G5 DG/HSI equipment, with the exact installation determined by the approved configuration.
| Installation role | What the buyer should confirm |
|---|---|
| Attitude | Whether the aircraft/configuration and intended use are covered by the STC and required retained instruments. |
| DG / heading | Applicable magnetometer, heading interfaces and approved equipment connections. |
| HSI | Approved navigation source/interface and the exact equipment combination permitted by the installation data. |
| Dual G5 | The complete approved configuration, including any limitations and retained mechanical instruments. |
Important: The STC Has Installation Limitations
The FAA-issued STC document includes limitations and conditions. Among them, the installation requires retention of the mechanical airspeed indicator, altimeter and vertical speed indicator. It also states that installations outside the configurations approved by the STC require separate airworthiness approval.
For IFR-approved aircraft, the STC document also includes conditions concerning retention of existing attitude or rate-of-turn instruments depending on how the G5 is installed. Always use the current approved data for the specific installation rather than relying on an old summary of the STC.
What Is a Garmin G5 STC Permission Letter?
Having access to an STC number is not the same thing as having unrestricted rights to use the STC data. Garmin’s current installation manual states that a permission letter to use the STC data is available for each authorized G5 installation and directs installers to obtain it through the Garmin installation process.
What About the GAD 29B?
The GAD 29B is relevant to certain G5 installations involving heading/course information and interfaces with other Garmin equipment. The important point is that the module should not be added merely because another aircraft uses one.
Garmin’s installation manual defines the approved interfaces and equipment combinations. Check the current manual for the exact installation rather than treating the GAD 29B as a universal G5 requirement.
G5 Software Updates Can Affect the Approved Configuration
The approval story does not end when the G5 is installed. Garmin continues to issue software and STC-related service bulletins. In 2026, Garmin documented G5 software version 8.70 under STC SA01818WI, with the applicable certification authorization identified as STC SA01818WI MDL Revision 34. Garmin also identifies maintenance and flight-manual documentation revisions that apply before return to service following that update.
Garmin’s current software collection lists G5 certified-aircraft software version 8.70, dated July 17, 2026.
G5 STC vs “TSO Approved”: Do Not Mix the Terms
STC and TSO are different approval concepts. The G5 installation in a certificated aircraft is governed by the applicable installation approval and data. A TSO authorization, where applicable to an article, is not by itself a blanket installation approval for a particular aircraft.
| Term | What it addresses |
|---|---|
| STC | A specific approved change to an aircraft type design, subject to its approved scope and limitations. |
| AML | The list of aircraft models/configurations covered by an AML STC. |
| TSO/TSOA | Authorization associated with an article meeting a Technical Standard Order specification; it does not by itself answer aircraft installation eligibility. |
| Installation manual | Provides the technical installation data and approved interfaces applicable to the STC installation. |
What Buyers Should Check Before Ordering a Certified G5
- Exact aircraft make and model.
- Whether the aircraft is covered by the current AML.
- Desired G5 role: attitude, DG, HSI or supported combination.
- Existing navigator and avionics.
- Autopilot interface requirements.
- Required retained instruments.
- Current installation manual and approved revisions.
- STC permission and installation documentation.
- Current software/service-bulletin status.
- Who will determine and approve the final installation.
Jet Aviation Spare Parts G5 Options
Jet Aviation Spare Parts carries G5 equipment for certified-aircraft applications, including:
- G5 Electronic Flight Instrument Kit with LPM for Certified Aircraft
- G5 Electronic Flight Instrument HSI with GPS/NAV Interface and LPM
For broader installation planning, read the Garmin G5 Installation Guide. It covers the wider installation decision, while this article focuses specifically on what SA01818WI means.
Planning a Garmin G5 Upgrade?
Confirm the aircraft, AML coverage, intended G5 role, interfaces and current approved documentation before ordering equipment or beginning installation.
View G5 Kit Read G5 Installation GuideFrequently Asked Questions
It is Garmin’s Part 23 AML Supplemental Type Certificate for approved installation of the G5 Electronic Flight Instrument on aircraft covered by the applicable Approved Model List.
No. The AML identifies the aircraft models/configurations covered by the approval. The specific installation must also follow the approved configuration and interfaces.
A physical fit is not the same as an approved installation. For a certificated aircraft, verify the aircraft’s eligibility and the applicable STC installation data.
No. Garmin states that only the interfaces between the G5 and equipment listed in the installation manual are approved by the STC.
No. Autopilot eligibility and interfaces must be evaluated against the applicable approved configuration and, where relevant, the separate autopilot approval.
The applicable STC includes installations for aircraft approved for IFR operations, subject to the specific approved configuration and limitations. The installation must follow the current approved data.
Because approved software and documentation can change. Garmin’s 2026 G5 service bulletin identifies software 8.70 under SA01818WI and specifies applicable documentation revisions for affected installations.