Garmin Autopilot Service Bulletin Released

Garmin has identified an issue with the GFC 500 that may result in an uncommanded automatic trim runaway when the autopilot is first engaged.

Garmin has identified an issue with the GFC 500 that may result in an uncommanded automatic trim runaway when the autopilot is first engaged. [Credit: Garmin]

If your light sport aircraft has a Garmin GFC 500 autopilot in it, take note. Garmin has identified an issue with the GFC 500 that may result in an uncommanded automatic trim runaway when the autopilot is first engaged.

According to Garmin, the GFC 500 autopilot with optional auto trim can be found in certified, experimental and light sport aircraft, including certified installations installed with optional GSA 28 pitch trim in accordance with Garmin’s supplemental type certificate, STC SA01866W. 

The company is working to fix this issue for certified installations in a future software update, which is expected by the end of Q4 2022.

In the meantime, in accordance with Service Alert 22109 Revision A, operators of certified installations of the GFC 500 need to pull and collar the autopilot circuit breaker and placard the autopilot as “inoperative” prior to further flight.

Garmin Service Bulletin 22112 Revision A requires operators of experimental and light sport aircraft to update system software or disable the autopilot or trim control prior to further flight.

Operators should contact a Garmin dealer regarding reactivation of the GFC 500 autopilot with the optional pitch trim configured off in accordance with recommended Service Bulletin 22110 Revision A.

Meg Godlewski has been an aviation journalist for more than 24 years and a CFI for more than 20 years. If she is not flying or teaching aviation, she is writing about it. Meg is a founding member of the Pilot Proficiency Center at EAA AirVenture and excels at the application of simulation technology to flatten the learning curve. Follow Meg on Twitter @2Lewski.

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