At 2043 ZT on 13 October you are in DR position LAT 43°57.3' S, LONG 147°16.0' E, when you observe an amplitude of Venus. The planet is about one Sun's diameter above the horizon and bears 236.2°pgc. The variation is 15°E. What is the gyro error?

Correct Answer: Option C — 0.0°

Computing the true bearing of Venus at visible horizon altitude via amplitude tables and comparing it against the gyro compass bearing (pgc) establishes the compass correction. The exact alignment between calculated true and observed pgc values yields zero gyro error.