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DAC GDC-31 GPSS/Roll Steering Converter

Forkauto

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So after my panel install, I have a DAC GDC-31 GPSS/Roll steering converter for sale. I purchased it about 2.5 years ago and it has been working great. I paid over 3AMU’s for it plus another 1AMU for install. I would like to get $1200/shipped CONUS. It will come with the GDC31, the radio coupler, and the annunciator. Here is a brief description from DAC:

The GDC31 output signal connects to the heading error input of the aircraft’s existing autopilot. The GDC31 mimics the heading error signal of the aircraft’s installed HSI or DG. The GDC31 does not reduce or otherwise alter any existing safety features of the autopilot, such as bank limiting, rate limiting and protection from a hard over. The GDC31 provides lateral (roll) data only (no pitch data is supplied by the GDC31).

The pilot simply selects between heading mode and GPS mode by using the switch / annunciator. In heading mode, the autopilot operates as always, tracking the heading bug of the HSI or DG. In GPS mode, the GDC31 RSS signal drives the autopilot’s heading channel. The GDC31 calculates the correct course intercept angle from the data supplied by the GPS, smoothly guiding the aircraft onto the course. The GDC31 then holds the aircraft on the selected course. If the GPS is programmed with Flight Plan data, the GDC31 will calculate the new intercept angle at each waypoint change, intercepting and holding the new course without pilot intervention.

The GDC31 is designed to operate with both rate based and position based autopilots.

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jruhnke

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Install is not cheap, but having GPSS is a wonderful quality-of-life addition to an airplane with a legacy autopilot! $900 for the hardware is a great way to save a few $$.
 

Forkauto

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Install is not cheap, but having GPSS is a wonderful quality-of-life addition to an airplane with a legacy autopilot! $900 for the hardware is a great way to save a few $$.
I paid 1k to have it initially installed. Truth be told, I like the way this unit operates over the way the G5 goes to GPSS mode with the push twist push. If I had to do over again, I probably would have kept it installed and just used it for GPSS instead of the G5. It would be nice if Garmin offered an input to a switch on the yoke for on/off of roll steering operation
 

philiplane

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The price killer on a used GDC31 is the cost of the permission letter from DAC needed to move it to another plane. Last I knew, it was over $1000.
 
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