单项选择题

Compass deviation is caused by（）.

A.magnetism from the earth's magnetic field
B.misalignment of the compass
C.magnetism within the vessel
D.a dirty compass housing

<上一题目录下一题>

热门试题

单项选择题

Before a magnetic compass is adjusted certain correctors must be checked to ensure that they are free of permanent magnetism. These correctors are the（）.

A.fore-and-aft and athwartships magnets
B.dip needle and heeling magnet
C.heeling magnet and Flinders bar
D.Flinders bar and quadrantal spheres

单项选择题

Based on your 2209 fix，which would be a warning that you are being set down on Block Island Sound South Entrance Obstruction Lighted BIS Buoy? （）

A.Decreasing loran readings on 9960-W
B.Visual bearings of Montauk Point Lt. changing to the left
C.Increasing bearings of Southeast Point Light
D.Decreasing soundings