The System Fifty is a two-axis autopilot which includes heading pre-select, turn command (which will give up to 90% standard rate turn), VOR / LOC tracking, back course tracking, a gain enhancement feature for tracking GPS Navigation analog left / right deviation signals, altitude hold, and pitch trim indicator lights.
Feb 02, 2017 Missed the 'we bought. Yea, do not install without the STC. Stec will bench check and rekit the autopilot to make sure you have everything. The STC specific parts list pretty much has to come from them, you can call and ask for it - they may or may not give it to you. The S-Tec System 55X incorporates the GPS Roll Steering and tracking with glide slope capture and track, VOR/localizer/back course intercept and tracking, and vertical speed commands. The System 55X Computer/Programmer has an LCD digital display and is designed for mounting in the standard avionics stack.
To utilize GPS roll steering (GPSS) commands, an additional ST-901 GPSS converter may be required to feed the autopilot with compatible steering signals. The ST-901 GPSS converter is not required for GPSS when integrating to an Aspen EFD system or Garmin G500/600 EFIS.
A compatible DG or HSI is required for the heading pre-select function or when adding the optional ST-901 GPSS converter.
Building block concept allows upgrading to a FiftyFiveX two-axis system.