Are the S-Tec autopilots capable of flying WAAS approaches from the Garmin GNS-430/530W WAAS series systems?
Yes, but please note the following considerations. For the S-Tec System 20 or 40, these systems are roll axis only. However, if equipped with a GPSS converter, these systems will follow the lateral steering commands from the GPS for a WAAS approach. Vertical guidance is pilot controlled. For the S-Tec System 30 or 50, these systems are roll axis and altitude hold only. However, with a GPSS converter, these systems will follow the lateral steering commands from the GPS for a WAAS approach. Vertical guidance is pilot controlled. For the Systems 55, 55X, 60-2, 60PSS, or 65, these systems will track the lateral deviation from the GPS navigator in the Approach (APR) mode and the vertical deviation in the Glideslope (GS) mode. If you are using a 55X or other autopilot systems equipped with a GPSS converter, they will not couple to a WAAS approach in GPSS mode. To follow both the vertical and horizontal deviations of a WAAS approach, the autopilot must be in Approach (APR) mode and Glideslope