The Cessna 177 is not offered in the current list of FG aircraft, nor is it in the repository. A sleek looking aircraft, I search for "Cessna 177 Flight Gear" yielded such model, within the archive of a flight gear installation. Looking into this further, I found a model situated within the "AI" folder of a newer (3+) FG distribution.
Here is the model imported in its current form into Flight Gear, at my Flight Gear One website.
https://sites.google.com/site/flightgea ... cessna-177