In the real world, this deviation is roughly 15 degrees per hour - but in FS2K2, values of 120 degrees/hour are no exception! Here's how you fix it. Open up FS2002.cfg with your favorite text editor and look for the line: "GyroEffect=1.000000" Change it to something more reasonable, e.g. "GyroEffect=0.125000", and presto!
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