60. As you pass through the Chesapeake Bay Bridge and Tunnel, you take a bearing of 047°pgc along trestle C when it is in line. The helmsman reports the vessel's heading as 316° pgc and 329°psc. What is the deviation on that heading?

The gyro error is determined by comparing the observed bearing of a known true bearing. Gyro error is then used to correct the gyro heading to true heading. Compass error is calculated as the difference between true and standard compass heading. Finally, deviation is found using the equation CE = Var + Dev, resulting in a deviation of 1W.