Bush flying in Alaska with the Hughes 500D and other helicopters with Mag Compass only or at best a Directional Gyro......with upwards of 20 Degrees Variation and some aircraft caused Deviation....and in the very far north along and beyond the Arctic Ocean coast line....with no discernible land features in sight.....life could bet a bit worrisome at times.
Sense of Direction could be a real quandary as looking a route that was clearly north/south or east/west....and having a Compass reading well off of that was a hard thing to accept.
Then add in near white out conditions and a featureless surface.....it was great fun.