Summary
The FAA is revising a notice of proposed rulemaking (NPRM) that applied to various airplanes modified with a certain configuration of the Garmin GFC 500 Autopilot System installed per Supplemental Type Certificate (STC) No. SA01866WI. This action revises the NPRM by removing airplane models from and adding airplane models to the applicability. The FAA is proposing this airworthiness directive to address the unsafe condition on these products. Since this action would expand the applicability for the required action as proposed in the NPRM, the agency is requesting comments on this SNPRM.