 
253.
1.
2.
3.
4.
254.
255.
256.
257.
Which of the following methods
should you use to convert compass
courses to true courses?
Add deviations and variations,
regardless of their direction,
to the compass course
Subtract deviations and
variations, regardless of their
direction, to the compass
course
Add easterly deviation and
variation to the compass course
and subtract westerly variation
and deviation from the compass
course
Subtract easterly deviation and
variation from the compass
course and add westerly
deviation and variation to the
compass course
If the magnetic heading is 255° and
the variation is 5°W, what is the
approximate true course?
1.
250°
2.
251°
3.
259°
4.
260°
If the compass course is 170°, the
variation is 15°E, and the
deviation is 5°W, what is the true
course?
1.
150°
2.
160°
3.
180°
4.
190°
If the variation is 5°W and the
deviation is 10°E, what compass
course must be steered to make good
a course of 090°T?
1.
075°
2.
085°
3.
095°
4.
105°
If the compass course is 270°, the
variation is 10°E, and the
deviation is 5°E, what is the
magnetic course of the ship?
1.
255°
2.
265°
3.
275°
4.
290°
250.
A ship is steering a compass course
of 180° making good a true course
of 176°. If the deviation is 2°E,
what is the variation?
1.
2°E
2.
6°E
3.
2°W
4.
6°W
IN ANSWERING QUESTIONS 259 THROUGH 262
REFER TO FIGURE 28 IN THE TEXT, MAGNETIC
COMPASS DEVIATION TABLE.
259.
If the true course is 195° and the
variation is 5°W (DG OFF), what is
the approximate compass course?
260
261,
262.
263.
264.
1.
199.5°
2.
200.5°
3.
204.5°
4.
205.5°
When variation is 10°W (DG OFF)
what is the deviation for a true
heading of 275°?
1.
0.0
2.
.2W
3.
.5W
4.
1.0W
When variation is 5°E (DG OFF),
what is the compass course for a
true course of 135°?
1.
127.5°
2.
132.5°
3.
137.5°
4.
142.5°
What is the true heading if the
magnetic heading is 240° with a
variation 7°E (DG ON)?
1.
231°
2.
235°
3.
245°
4.
247°
When a ship is under way, the
ship's compasses should be compared
at least how often?
1.
Once a watch
2.
Every 4 hours
3.
4.
Every course change only
Every 1/2 hour and at each
course change
At least how often must the
magnetic compass be adjusted?
1.
Every time the ship gets under
way
2.
Once a year
3.
Once a quarter
4.
Only when the ship leaves the
shipyard
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