|
You are on course 355°T and take a relative bearing of a lighthouse of 275°.
What is the true bearing of the lighthouse? |
085° |
270° |
280° |
080° |
|
You are on course 222°T and take a relative bearing of a lighthouse of 025°.
What is the true bearing to the lighthouse? |
247° |
315° |
197° |
335° |
|
You are on course 357°T and take a relative bearing of a lighthouse of 180°.
What is the true bearing to the lighthouse? |
227° |
177° |
363° |
003° |
You are on course 344°T and take a relative bearing of a lighthouse of 270°.
What is the true bearing to the lighthouse?
|
074°
|
090°
|
254°
|
016° |
|
You are on course 180°T and take a relative bearing of a lighthouse of 225°.
What is the true bearing of the lighthouse? |
270° |
045° |
180° |
135° |
You take a bearing of 264° of a lighthouse. What bearing of another object
would give the best fix?
|
081°
|
350°
|
120°
|
289° |
|
You take a bearing of 086° of a lighthouse. What bearing of another object
would give the best fix? |
000° |
066° |
112° |
271° |
|
You take a bearing of 176° of a lighthouse. Which bearing of another object
would give the best fix? |
079° |
151° |
176° |
292° |
|
You take a bearing of 176° of a lighthouse. What bearing of another object
would give the best fix? |
000° |
021° |
189° |
272° |
|
You take a bearing of 356° of a lighthouse. What bearing of another object
would give the best fix? |
201° |
013° |
082° |
176° |
|
You take a bearing of 356° of a lighthouse. Which bearing of another object
would give the best fix? |
178° |
256°
|
342° |
013° |
|
You take a bearing of 313° and 076° of two objects. Which bearing of a third
object will give the best fix? |
014° |
133° |
339° |
255° |
|
You take a bearing of 191° and 313° to two objects. Which bearing of a third
object will give the best fix? |
022° |
131° |
211° |
249° |
|
You take a bearing of 086° of a lighthouse. Which bearing of another object
would give the best fix? |
261° |
291° |
242° |
196° |
You take a bearing of 264° of a lighthouse. Which bearing of another object
would give the best fix?
|
239°
|
059°
|
291°
|
182° |
|
You take a bearing of 191° and 313° to two objects. Which bearing of a third
object will give the best fix? |
001° |
069° |
209° |
356° |
|
You take a bearing of 142° and 259° of two objects. Which bearing of a third
object will give the best fix? |
234° |
201° |
081° |
238° |
|
You take a bearing of 142° and 259° of two objects. What bearing of a third
object will give the best fix? |
084° |
281° |
019° |
166° |
|
You take a bearing of 043° and 169° of two objects. What bearing of a third
object will give the best fix? |
201°
|
356° |
144° |
102° |
|
You take a bearing of 043° and 169° of two objects. What bearing of a third
object will give the best fix? |
309° |
073° |
356° |
192° |
|
You take bearings of 313°T and 076°T on two objects. Which bearing of a
third object will give the best fix? |
048°T |
101°T |
142°T |
187°T |
A position on the Earth has a longitude of 74°10'E. Its celestial counterpart
would have a __________.
|
GHA
of 285°50'
|
SHA
of 285°50'
|
LHA
of 74°10'E
|
SHA
of 74°10' |
|
Given are the courses and speeds of 4 vessels. The navigator of which vessel
would be required to know the actual time of meridian transit in order to
take an accurate observation at LAN? |
C
356°T, Sp 5 knots |
C
192°T, Sp 23 knots |
C
278°T, Sp 6 knots |
C
099°T, Sp 17 knots |
|
Given are the courses and speeds of 4 vessels. The navigator of which vessel
would be required to know the actual time of meridian transit in order to
take an accurate observation at LAN ? |
C
101°T, Sp 7 knots |
C
349°T, Sp 25 knots |
C
018°T, Sp 6 knots |
C
079°T, Sp 24 knots |
|
Given are the courses and speeds of 4 vessels. The navigator of which vessel
would be required to know the actual time of meridian transit in order to
take an accurate observation at LAN? |
C
095°T, Sp 30 knots |
C
268°T, Sp 22 knots |
C
162°T, Sp 27 knots |
C
356°T, Sp 5.5 knots |
Given are the courses and speeds of 4 vessels. The navigator of which vessel
would be required to know the actual time of meridian transit in order to
take an accurate observation at LAN?
|
C
112°T, Sp 4 knots
|
C
291°T, Sp 25 knots
|
C
166°T, Sp 24 knots
|
C
013°T, Sp 7 knots |
|
The altitude at LAN may be observed by starting several minutes in advance
and continuing until a maximum altitude occurs. This procedure should not
be used __________. |
on
a fast vessel on northerly or southerly headings |
if
the vessel is stopped or making bare steerageway |
when
the declination and latitude are of different names |
when
the declination is greater than and the same name as the latitude |
|
In order for a star to be used for a sight at lower transit, the star must
__________. |
have
a declination equal to or greater than your latitude |
have
the SHA equal to or less than the LHA |
have
a GHA of 180° |
be
circumpolar |
|
A body can only be observed at lower transit when __________. |
the
body is circumpolar |
the
algebraic sum of the colatitude and declination exceeds 90° |
the
declination is the opposite name to the latitude |
the
observer is in high latitudes above either polar circle |
|
When taking stars, those bodies to the east and west will __________. |
change
altitude rapidly |
remain
in an almost fixed position |
change
altitude slowly |
appear
to be moving in the plane of the horizon |
|
When taking an amplitude, the Sun's center should be observed on the visible
horizon when __________. |
the
declination is of a different name from the latitude |
the
Sun is near or at a solstice |
in
high latitudes |
the
Sun's declination is at or near 0° |
|
An amplitude of the Sun in high latitudes __________. |
should
only be observed when the Sun's lower limb is above the horizon |
is
most accurate before sunrise |
is
most accurate after sunset |
is
most accurate when the Sun's center is observed on the visible horizon |
|
What is the longitude of the geographical position of a body whose Greenwich
hour angle is 210°30'? |
30°30'E |
120°30'W |
149°30'E |
59°30'W |
|
What is the geographic longitude of a body whose GHA is 232°27'? |
61°52'E |
61°52'W |
52°27'E |
127°33'E |
|
What is the geographic longitude of a body whose GHA is 215°15'? |
35°15'E |
35°15'W |
144°45'E |
144°45'W |
|
The line of position determined from a sight with an observed altitude (Ho)
of 88°45.0' should be __________. |
plotted
by using an intercept from an assumed position |
plotted
as an arc around the GP of the body |
calculated
as a longitude line |
reduced
to the meridian and plotted as a latitude line |
|
When plotting a circle of equal altitude for a high altitude sight, the
radius of the circle is determined by the formula __________. |
180°
- GHA |
z
- d |
90°
- Ho |
GHA
- LHA |
|
The line of position should be plotted as a circle around the GP of the
body when the Ho exceeds what minimum value? |
80° |
83° |
85° |
87° |
|
The GP of a body for a high altitude sight is determined from the declination
and the __________. |
Greenwich
hour angle |
zenith
distance |
azimuth |
right
ascension |
|
The center of a circle of equal altitude, plotted on the surface of the
Earth, is the __________. |
geographical
position of the body |
assumed
position of the body |
assumed
position of the observer |
dead
reckoning position of the observer |
|
The GP of a body for a high altitude sight is determined from the declination
and the __________. |
sidereal
hour angle |
observed
altitude |
Greenwich
hour angle |
right
ascension |
|
The GP of a body for a high altitude sight is determined from the Greenwich
hour angle and the __________. |
zenith
distance |
declination |
azimuth
angle |
circle
of equal altitude |
|
What is the major problem with taking high altitude sun observations? |
The
tables are not as accurate due to inherent errors in the spherical triangle
at high altitudes. |
Rapidly
changing altitudes make it difficult to get an accurate altitude. |
Possible
errors due to unusual refraction may exist. |
It
is difficult to establish the point where the sextant is vertical to the
horizon. |
|
What is the major advantage of high altitude observations? |
The
semidiameter correction of the sextant altitude is eliminated. |
Errors
due to unusual parallax are eliminated. |
The
same body can be used for a fix from observations separated by several minutes. |
The
declination is the only information needed from the almanac. |
|
Why are low altitude sun sights not generally used? |
Modern
sight reduction tables are not complete for low altitudes below 5°. |
The
glare on the horizon causes irradiation errors. |
Errors
due to unusual refraction may exist. |
Sextants
may have large errors at small angles of elevation. |
|
In high latitudes, celestial observations can be made over a horizon covered
with pack ice by bringing the sun tangent to the ice and __________. |
using
a dip correction based on the height of eye above the ice |
doubling
the semidiameter correction |
using
a dip correction from table 22 in Bowditch Vol. II |
adding
30° of arc to the sight |
|
At morning stars, the first stars that should be observed are those with
an azimuth in which quadrant? |
Western |
Eastern |
Northern |
Southern |
|
At morning stars, the last stars that should be observed are those with
an azimuth in which quadrant? |
Western |
Eastern |
Northern |
Southern |
|
At evening stars, the first stars that should be observed are those with
an azimuth in what quadrant? |
Western
|
Northern |
Eastern
|
Southern |
|
At evening stars, the last stars that should be observed are those with
an azimuth in what quadrant? |
Northern |
Eastern |
Western |
Southern |
|
In general, the most effective period for observing stars and planets occurs
during the darker limit of __________. |
astronomical
twilight |
nautical
twilight |
civil
twilight |
sunset |
A dead reckoning (DR) plot __________.
|
must
be plotted using magnetic courses |
ignores
the effect of surface currents |
is
most useful when in sight of land |
may
be started at an assumed position |
A dead reckoning (DR) plot __________.
|
should
be replotted hourly
|
should
be started each time the vessel's position is fixed
|
must
utilize magnetic courses
|
must
take set and drift into account |
|
Discounting slip, if your vessel is turning RPM for 10 knots and making
good a speed of 10 knots, the current could be __________. |
with
you at 10 knots |
with
you at 2 knots |
against
you at 10 knots |
slack |
|
A current perpendicular to a vessel's track has the greatest effect on the
vessel's course made good __________. |
at
high vessel speeds |
at
low vessel speeds |
in
deep water |
in
shallow water |
|
The type of current which will have the greatest effect on the course made
good for your vessel is __________. |
one
that flows at nearly right angles to your course steered |
a
rotary current in which the direction of current flow constantly changes |
one
flowing in the same direction as your course steered |
one
flowing in the opposite direction as your course steered |
|
You are heading in a northerly direction when you come across an easterly
current. Your vessel will __________. |
be
pushed to port |
decrease
in engine speed |
remain
on course |
be
pushed to starboard |
|
At 0000 you fix your position and plot a new DR track line. At 0200 you
again fix your position and it is 0.5 mile east of your DR. Which statement
is TRUE? |
You
must increase speed to compensate for the current. |
The
current cannot be determined. |
The
current is westerly at 0.5 knot. |
The
drift is 0.25 knot. |
|
At 0000 you fix your position and plot a new DR track line. At 0200 you
again fix your position and it is 0.5 mile west of your DR. Which statement
is TRUE? |
The
set is 090°, drift 0.5 knot. |
The
set is 270°, drift 1.0 knot. |
The
set is 270°, drift 0.5 knot. |
The
set is 270°, drift 0.25 knot. |
|
At 0000 you fix your position and change course to 090°T. At 0030 you again
fix your position and it is 0.5 mile east of your DR. Which statement is
TRUE? |
The
current is easterly. |
You
should alter course to the right to regain the track line. |
The
current is perpendicular to your track line. |
The
drift is 0.5 knot. |
|
At 0000 you fix your position and change course to 270°T. At 0030 you again
fix your position, and it is 0.5 mile east of your DR. Which statement is
TRUE? |
The
set is 270°, drift 1.0 knot. |
The
set is 090°, drift 0.5 knot. |
The
set is 270°, drift 0.5 knot. |
The
set is 090°, drift 1.0 knot. |
|
Which statement concerning current is TRUE? |
Current
can be determined by measuring the direction and distance between simultaneous
EP and DR positions. |
The
distance between a simultaneous DR position and fix is equal to the drift
of the current. |
The
drift of the current should be averaged out on a one hour basis. |
After
the current is determined, it should not be used for further plotting because
it is an unknown variable. |
|
Which error is NOT included in the term "current" when used in
relation to a fix? |
Poor
steering |
Leeway |
Ocean
currents |
Known
compass error |
|
You are proceeding up a channel at night. It is marked by a range which
bears 185°T. You steady up on a compass course of 180° with the range in
line dead ahead. This indicates that you(r) __________. |
are
being affected by a southerly current |
must
come right to get on the range |
course
is in error |
compass
has some easterly error |
|
You are steering a southerly course, and you note that the chart predicts
an easterly current. Without considering wind, how may you allow for the
set? |
Decrease
your speed |
Increase
your speed |
Head
your vessel slightly to the right |
Head
your vessel slightly to the left |
|
Your vessel is making way through the water at a speed of 12 knots. Your
vessel traveled 30 nautical miles in 2 hours 20 minutes. What current are
you experiencing? |
A
following current of 0.9 knot |
A
following current at 2.0 knots |
A
head current of 2.0 knots |
A
head current of 0.9 knot |
|
When possible, a DR plot should always be started from where? |
A
known position |
An
assumed position |
Any
position |
None
of the above |
|
The direction in which a vessel is steered is the course. The path actually
followed is the __________. |
route |
course
over the ground |
heading |
track |
|
The paths of intended travel between three or more points is the __________. |
bearing |
track |
course |
course
over the ground |
|
The direction in which a vessel should be steered between two points is
the __________. |
course |
bearing |
course
over the ground |
heading |
|
The direction a vessel is pointed at any given time is the __________. |
heading |
course |
track |
course
over the ground |
The path that a vessel is expected to follow, represented on a chart by
a line drawn from the point of departure to the point of arrival, is the
__________.
|
estimated
course
|
DR
plot
|
heading
|
track
line |
|
The difference between the DR position and a fix, both of which have the
same time, is caused by __________. |
deviation |
current |
leeway |
variation |
|
You plot a fix using three lines of position and find they intersect in
a triangle. You should plot the position of the vessel __________. |
in
the geometric center of the triangle |
outside
of the triangle |
on
the line of position from the nearest object, between the other two lines
of position |
anywhere
in the triangle |
|
In illustration D051NG below, why was the position labeled "E"
plotted? |
the
vessel's position was fixed at 1145 |
the
position is a running fix |
a
dead reckoning position is plotted for each speed change |
a
dead reckoning position is plotted within a half-hour of each course change |
|
In illustration D051NG below what is indicated by the position labeled "C"? |
estimated
position |
fix |
running
fix |
dead
reckoning position |
|
You are navigating in pilotage waters using running fixes. The maximum time
between fixes should be about __________. |
5
minutes |
1
hour |
30
minutes |
4
hours |
|
How many fixed objects are needed to plot a running fix? |
None |
One |
Two |
Three |
|
In illustration D051NG below, why was the position labeled "C"
plotted? |
running
fixes are better estimates of true position than dead-reckoning positions |
the
vessel's speed changed |
the
vessel's course changed form due North to due East |
All
of the above. |
You should plot your dead reckoning position __________.
|
only
in pilotage waters
|
from
every fix or running fix
|
every
three minutes in pilotage waters
|
from
every estimated position |
|
You should plot a dead reckoning position after every __________. |
fix
or running fix |
course
change |
speed
change |
All
of the above. |
|
In illustration D051NG below, why was the position labeled "D"
plotted? |
the
vessel's speed changed at 1125 |
a
dead reckoning position is plotted within 30 minutes of a running fix |
a
dead reckoning position is plotted for each course change |
All
of the above. |
|
A position obtained by applying ONLY your vessel's course and speed to a
known position is a __________. |
dead-reckoning
position |
running
fix |
fix |
probable
position |
|
Your dead reckoning position should be plotted __________. |
when
coming on or going off soundings |
at
least every hour on the hour in the open waters of the sea |
whenever
an estimated position is plotted |
when
it agrees with your GPS position |
|
You plot a fix using three lines of position and find they intersect in
a triangle. The actual position of the vessel __________. |
may
be inside or outside of the triangle |
is
outside of the triangle |
is
the geometric center of the triangle |
may
be anywhere in the triangle |
|
You are plotting a running fix in an area where there is a determinable
current. How should this current be treated in determining the position? |
The
set should be applied to the second bearing. |
The
current should be ignored. |
The
course and speed made good should be determined and used to advance the
LOP. |
The
drift should be added to the ship's speed. |
|
Which statement about an estimated position is TRUE? |
It
is more reliable than a fix based on radar bearings. |
When
a 3-LOP fix plots in a triangle, the center of the triangle is the estimated
position. |
It
may be based on a single LOP or questionable data. |
It
is usually based on soundings. |
|
A position that is obtained by using two or more intersecting lines of position
taken at nearly the same time, is a(n) __________. |
running
fix |
dead-reckoning
position |
fix |
estimated
position |
|
You are taking bearings on two known objects ashore. The BEST fix is obtained
when the angle between the lines of position is __________. |
45° |
30° |
60° |
90° |
|
Which position includes the effects of wind and current? |
Leeway
position |
Set
position |
Dead
reckoning position |
Estimated
position |
|
A position that is obtained by applying estimated current and wind to your
vessel's course and speed is a(n) __________. |
fix |
dead
reckoning position |
estimated
position |
None
of the above |
Which position includes the effects of wind and current?
|
Set
position
|
Estimated
position
|
Leeway
position
|
Dead
reckoning position |
|
You are running parallel to the coast and estimate that the current is against
you. In plotting a running fix using bearings from the same object on the
coast, the greatest safety margin from inshore dangers will result if what
speed is used to determine the fix? |
Maximum
speed estimate |
Average
speed estimate |
Minimum
speed estimate |
A
running fix should not be used under these conditions. |
|
You are running parallel to the coast and take a running fix using bearings
of the same object. If you are making less speed than used for the running
fix, in relation to the position indicated by the fix, you will be __________. |
closer
to the coast |
farther
from the coast |
on
the track line behind the fix |
on
the track line ahead of the fix |
|
You are running parallel to the coast and plotting running fixes using bearings
of the same object. You are making more speed than assumed for the running
fix. In relation to the position indicated by the fix you will be __________. |
on
the track line behind the fix |
on
the track line ahead of the fix |
farther
from the coast |
closer
to the coast |
|
A navigator fixing a vessel's position by radar __________. |
can
use radar information from one object to fix the position |
should
never use radar bearings |
should
only use radar bearings when the range exceeds the distance to the horizon |
must
use information from targets forward of the beam |
|
When using a radar in an unstabilized mode, fixes are determined most easily
from __________. |
center
bearings |
tangent
bearings |
ranges |
objects
that are close aboard |
|
You are plotting a running fix. The LOP to be run forward is an arc from
a radar range, what technique should be used? |
The
distance between LOP's should be added to the radar range and a new arc
swung. |
The
position of the object observed should be advanced to the new time and a
new arc swung using the radius of the old arc. |
The
arc should be converted into a straight line using offsets and then run
forward. |
An
arc should never be run forward. |
|
A chart position enclosed by a square is a(n) __________. |
dead
reckoning position |
running
fix |
estimated
position |
fix |
|
A chart position enclosed by a semi-circle is a(n) __________. |
fix |
running
fix |
estimated
position |
dead
reckoning position |
|
What describes an accurate position that is NOT based on any prior position? |
Dead-reckoning
position |
Fix |
Estimated
position |
Running
fix |
|
You determine your vessel's position by taking a range and bearing to a
buoy. Your position will be plotted as a(n) __________. |
dead-reckoning
position |
running
fix |
estimated
position |
fix |
A single line of position combined with a dead-reckoning position results
in a(n) __________.
|
fix |
assumed
position |
running
fix |
estimated
position |
|
A position obtained by taking lines of position from one object at different
times and advancing them to a common time is a(n) __________. |
estimated
position |
running
fix |
fix |
dead-reckoning
position |
|
A vessel's position should be plotted using bearings of __________. |
fixed
objects |
fixed
known objects on shore |
buoys
close at hand |
All
of the above. |
|
Lines of position may be __________. |
hyperbolas |
arcs |
straight
lines |
All
of the above. |
|
A line connecting all possible positions of your vessel at any given time
is a __________. |
fix |
longitude
line |
line
of position |
latitude
line |
|
A line of position is __________. |
not
used in a running fix |
a
line connecting two charted objects |
the
position of your vessel |
a
line on some point of which the vessel may be presumed to be located |
|
A line of position formed by sighting two charted objects in line is called
a(n) __________. |
estimated
position |
relative
bearing |
track
line |
range
line |
|
A line of position derived by radar range from an identified point on a
coast will be a(n) __________. |
parabola |
arc |
line
parallel to the coast |
straight
line |
|
A radar range to a small, charted object such as a light will provide a
line of position in which form? |
Arc |
Hyperbola |
Parabola |
Straight
line |
|
A true bearing of a charted object, when plotted on a chart, will establish
a __________. |
line
of position |
range |
relative
bearing |
fix |
|
What is NOT an advantage of the rhumb line track over a great circle track? |
Easily
plotted on a Mercator chart |
Plots
as a straight line on Lambert conformal charts |
Negligible
increase in distance on east-west courses near the equator |
Does
not require constant course changes |
|
What is the major advantage of a rhumb line track? |
The
rhumb line is the shortest distance between the arrival and departure points. |
The
vessel can steam on a constant heading (disregarding wind, current, etc.). |
It
is easily plotted on a gnomonic chart for comparison with a great circle
course. |
It
approximates a great circle on east-west courses in high latitudes. |
|
When is the rhumb line distance the same as the great circle distance? |
The
rhumb line distance is always longer than the great circle distance. |
Course
090°T in high latitudes |
Course
045°T in low latitudes |
Course
180°T when you cross the equator |
|
In which voyage, between two points, is the rhumb line distance NOT approximately
the same as the great circle distance? |
The
two points are in high latitudes in the same hemisphere. |
The
two points are in low latitudes in the same hemisphere. |
One
point is near the equator, one point is in a high latitude, and both are
near the 180th meridian. |
The
two points are near the equator, but in different hemispheres. |
|
What is a characteristic of a rhumb line? |
The
course angle constantly changes to form the loxodromic curve. |
It
plots as a straight line on a Lambert conformal chart. |
It
cuts each meridian at the same angle. |
It
is the shortest distance between two points on the Earth. |
|
A great circle track provides the maximum saving in distance on __________. |
easterly
courses in high latitudes |
southerly
courses in high latitudes |
westerly
courses in low latitudes |
easterly
courses in low latitudes that cross the equator |
|
Except for N-S courses, and E-W courses on the equator, a great circle track
between two points, when compared to a rhumb line track between the same
two points, will __________. |
be
nearer to the pole in the Northern Hemisphere and nearer to the equator
in the Southern Hemisphere |
always
be nearer to the equator |
always
be nearer to the elevated pole |
be
nearer to the pole or the equator depending on the latitudes of the arrival
and departure positions |
|
The shortest distance between any two points on earth defines a __________. |
rhumb
line |
small
circle |
great
circle |
hyperbola |
|
What defines a great circle? |
The
smallest circle that can be drawn on the face of a sphere |
A
curved line drawn on a Mercator Chart |
A
course line that inscribes a loxodromic curve |
The
intersection of a plane passing through the center of a sphere. |
|
The latitude of the upper vertex of a great circle is 36°N. What is the
latitude of the lower vertex? |
36°S |
Cannot
be determined from the information given |
0° |
36°N |
|
A great circle crosses the equator at 141°E. It will also cross the equator
at what other longitude? |
141°W |
41°E |
39°W |
180°E |
|
A great circle crosses the equator at 162°E. It will also cross the equator
at what other longitude? |
62°E |
18°W |
126°W |
162°W |
|
A great circle crosses the equator at 134°E. It will also cross the equator
at what other longitude? |
46°W |
34°E |
134°W |
124°W |
|
A great circle crosses the equator at 173°E. It will also cross the equator
at what other longitude? |
173°W |
73°E |
73°W |
7°W |
|
A great circle crosses the equator at 127°W. It will also cross the equator
at what other longitude? |
127°E |
27°W |
53°E |
27°E |
|
A great circle crosses the equator at 93°W. It will also cross the equator
at what other longitude? |
177°W |
87°E |
13°E |
177°E |
|
A great circle crosses the equator at 17°W. It will also cross the equator
at what other longitude? |
17°E |
173°W |
163°E |
117°W |
|
A great circle crosses the equator at 157°W. It will also cross the equator
at what other longitude? |
57°E |
23°E
|
57°W |
157°E |
|
A great circle will intersect the equator at how many degrees of longitude
apart? |
0° |
90° |
45° |
180° |
|
The distance that a vessel travels from the time that the order to put engines
full astern until the vessel is dead in the water is known as __________. |
head
reach |
advance |
surge |
transfer |
|
The vertex of a great circle track is in LONG 109°E. An eastbound vessel
would cross the equator in LONG __________. |
19°E |
161°W |
161°E |
19°W |
|
The upper vertex of a great circle track is in LONG 156°00'E. Sailing eastward,
the great circle track will cross the equator in LONG __________. |
66°00'E |
114°00'W |
66°00'W |
110°00'W |
|
The distance in longitude from the intersection of a great circle and the
equator to the lower vertex is how many degrees of longitude? |
135° |
180° |
90° |
45° |
|
The longitude of the upper vertex of a great circle track is 169°E. What
is the longitude of the lower vertex? |
169°W |
076°E |
011°W |
101°W |
|
From LAT 07°12'N, LONG 80°00'W, to LAT 47°12'S, LONG 169°18'E, the initial
great circle course angle is 137.25°. How would you name this course? |
S
137.25°E |
N
137.25°W |
S
137.25°W |
N
137.25°E |
|
The initial great circle course angle between LAT 23°0034°00'S, LONG 18°00'E
is 063.8°. What is the true course? |
063.8°T |
243.8°T |
116.2°T |
296.2°T |
|
For navigational purposes, each great circle on the Earth has a length of
__________. |
3,600
miles |
21,600
miles |
12,500
miles |
5,400
miles |
Your vessel has changed course and is heading 285°T, you are on the charted
range and it appears as in illustration D048NG below. After several minutes
the range appears as in illustration D047NG below and your heading is still
285°T. What does this indicate? |
course
made good to the left of the DR track |
leeway
caused by a NE'ly wind |
south-setting
current |
north-setting
current |
|
You are on course 355°T and take a relative bearing of a lighthouse of 275°.
What is the true bearing of the lighthouse? |
085° |
280° |
270° |
080° |
|
You are on course 222°T and take a relative bearing of a lighthouse of 025°.
What is the true bearing to the lighthouse? |
247° |
315° |
197° |
335° |
|
You are on course 357°T and take a relative bearing of a lighthouse of 180°.
What is the true bearing to the lighthouse? |
227° |
363° |
003° |
177° |
|
You are on course 344°T and take a relative bearing of a lighthouse of 270°.
What is the true bearing to the lighthouse? |
090° |
074° |
254° |
016° |
|
You are on course 344°T and take a relative bearing of a lighthouse of 090°.
What is the true bearing to the lighthouse? |
016° |
074° |
254° |
270° |
|
You are on course 277°T and take a relative bearing of a lighthouse of 045°.
What is the true bearing to the lighthouse? |
038° |
232° |
315° |
322° |
|
A nautical mile is a distance of approximately how much greater than or
less than a statute mile? |
1/4
greater |
1/4
less |
1/7
less |
1/7
greater |
|
A nautical mile is a distance of approximately how much greater than or
less than a statute mile? |
1/7
greater |
1/7
less |
1/4
less |
1/4
greater |
|
You are outbound in a channel marked by a range astern. The range line is
309°T. You are steering 127°T and have the range in sight as shown in illustration
D047NG below. What action should you take? |
Come
left until the range comes in line then alter course to 125°T. |
Come
right to 129°T. |
Come
right to close the range then when on the range steer 129°T. |
Come
left until the range comes in line then alter course to 129°T. |
|
You are inbound in a channel marked by a range. The range line is 309°T.
You are steering 306°T and have the range in sight as shown in illustration
D048NG below. Which action should you take? |
Immediately
alter course to 309°T if the range is closing. |
Continue
on the present heading until the range is in line then alter course to the
right. |
Immediately
alter course to the left to bring the range in line. |
Immediately
alter course to the right to bring the range in line. |
|
You are inbound in a channel marked by a range. The range line is 040°T.
You are steering 036°T. The range is in sight as shown in illustration D047NG
below, and is closing. Which action should you take? |
Immediately
alter course to 040°T. |
Continue
on the present heading until the range is in line then alter course to the
left. |
Immediately
alter course to the right to bring the range in line. |
Continue
on course until the range is closed, then alter course to the right. |
|
You are inbound in a channel marked by a range. The range line is 216°T.
You are steering 213°T and have the range in sight as shown in illustration
D048NG below. Which action should you take? |
Immediately
alter course to the right to bring the range in line. |
Immediately
alter course to the left to bring the range in line. |
Continue
on the present heading until the range is in line then alter course to the
right. |
Immediately
alter course to 216°T if the range is closing. |
|
You are outbound in a channel marked by a range astern. The range line is
273°T. You are steering 090°T and have the range in sight as shown in illustration
D047NG below. What action should you take? |
Come
right to 093° T. |
Come
right to close the range then when on the range steer 093° T. |
Come
left until the range comes in line then alter course to 087° T. |
Come
left until the range comes in line than alter course to 093° T. |
|
You are inbound in a channel marked by a range. The range line is 133°T.
You are steering 129°T and have the range in sight as shown in illustration
D048NG below. Which action should you take? |
Immediately
alter course to the left to bring the range in line. |
Immediately
alter course to 133°T if the range is closing. |
Continue
on the present heading until the range is in line then alter course to the
right. |
Immediately
alter course to the right to bring the range in line. |
|
You are outbound in a channel marked by a range astern. The range line is
133°T. You are steering 315°T and have the range in sight as shown in illustration
D048NG below. What action should you take? |
Come
right until the range comes in line then alter course to 317°T. |
Come
left to 313°T. |
Come
right until the range comes in line then alter course to 313°T. |
Come
left to close the range then when on the range steer 313°T. |
|
You are entering port and have been instructed to anchor, as your berth
is not yet available. You are on a SW'ly heading, preparing to drop anchor,
when you observe the range lights as shown in illustration D047NG below,
on your starboard beam. What action should you take? |
ensure
your ship will NOT block the channel or obstruct the range while at anchor |
drop
the anchor immediately as a change in the position of the range lights will
be an indication of dragging anchor |
drop
the anchor immediately as the range lights mark an area free of obstructions |
NOT
drop the anchor until the lights are in line |
|
What is the relative bearing of an object broad on the port beam? |
235° |
315° |
270° |
300° |
|
Your vessel is entering port when you change course and steady up on a range
with the lights in line. After a few minutes you observe the range lights
as shown in illustration D047NG below. How should your heading be altered? |
right,
and when the range lights are in line again, steer to keep them dead ahead |
right,
and when the range lights are in line again, steer to keep them in line
fine on the port bow |
left,
and when the range lights are in line again, resume your original heading |
left,
and when the range lights are in line again, steer to keep them in line
fine on the starboard bow |
|
Your vessel is entering port and you have steadied up on a range, dead ahead,
in line with your keel. After a few minutes the range, still dead ahead,
appears as shown in illustration D047NG below. Which action should you take? |
Alter
heading to the left |
Alter
heading to the right |
Maintain
heading, keeping the range dead ahead |
Increase
speed |
|
You are inbound in a channel marked by a range. The range line is 309°T.
You are steering 306°T and have the range in sight as shown in illustration
D047NG below. The range continues to open. What action should you take? |
Alter
course to the left to close the range, then alter course to 309°T. |
Alter
course to the left until the range closes, then steer to the left of 306°T. |
Alter
course to the right to 309°T or more to bring the range in line. |
Maintain
course as it is normal for the range to open as you get close. |
|
What is the relative bearing of an object broad on the port bow? |
315° |
330° |
345° |
360° |
You are on course 180°T and take a relative bearing of a lighthouse of 225°.
What is the true bearing of the lighthouse?
|
270°
|
180°
|
045°
|
135° |
|
What is the relative bearing of an object broad on the starboard quarter? |
045° |
090° |
135° |
225° |
|
You are on course 027°T and take a relative bearing to a lighthouse of 220°.
What is the true bearing to the lighthouse? |
113° |
193° |
247° |
279° |
|
A relative bearing is always measured from __________. |
the
vessel's beam |
true
north |
the
vessel's head |
magnetic
north |
|
What is the relative bearing of an object dead astern? |
270° |
000° |
090° |
180° |
What is the relative bearing of an object sighted dead ahead?
|
180° |
090° |
015° |
000° |
|
What is the relative bearing of an object broad on the starboard bow? |
030° |
045° |
060° |
075° |
|
What is the relative bearing of an object broad on the starboard beam? |
090° |
045° |
060° |
075° |
|
What is the relative bearing of an object broad on the starboard quarter? |
090° |
105° |
135° |
150° |
|
What is the relative bearing of an object broad on the port quarter? |
195° |
225° |
240° |
265° |
|
What is the relative bearing of an object on the port beam? |
045° |
090° |
180° |
270° |
|
You are on course 030°T. The relative bearing of a lighthouse is 45°. What
is the true bearing? |
015° |
075°
|
345° |
255° |
|
You are underway in an area where the charted depth is 8 fathoms. You compute
the height of tide to be -4.0 feet. The draft of your vessel is 5.0 feet
(1.52 meters). You determine the depth of the water beneath your keel to
be __________. |
39
feet (11.9 meters) |
57
feet (17.4 meters) |
43
feet (13.1 meters) |
47
feet (14.3 meters) |
|
You are underway in a vessel with a draft of 7.0 feet (2.1 meters). The
charted depth for your position is 9 fathoms. You compute the height of
tide to be +3.0 feet (0.9 meters). You determine the depth of the water
beneath your keel to be __________. |
50
feet (15.3 meters) |
41
feet (12.6 meters) |
32
feet (9.8 meters) |
64
feet (19.6 meters) |
|
You are underway in a vessel with a draft of 6.0 feet. You are in an area
where the charted depth of the water is 4 fathoms. You would expect the
depth of water beneath your keel to be approximately __________. |
24
feet |
30
feet |
12
feet |
18
feet |
|
If a chart indicates the depth of water to be 6 fathoms and your draft is
6.0 feet, what is the depth of the water under your keel? (Assume the actual
depth and charted depth to be the same) |
6.0
feet |
26.5
feet |
30.0
feet |
56.5
feet |
|
When using horizontal sextant angles of three objects to fix your position,
an indeterminate position will result in which situation? |
The
vessel is outside of a triangle formed by the objects. |
The
objects lie in a straight line. |
The
vessel is inside of a triangle formed by the objects. |
A
circle will pass through your position and the three objects. |
|
When making landfall at night, the light from a powerful lighthouse may
sometimes be seen before the lantern breaks the horizon. This light is called
the __________. |
diffusion |
elevation |
loom |
backscatter |
|
When making landfall at night, you can determine if a light is a major light
or an offshore buoy by __________. |
the
intensity of the light |
the
color, because the buoy will have only a red or a green light |
checking
the period and characteristics against the Light List |
All
of the above. |
|
If several navigational lights are visible at the same time, each one may
be positively identified by checking all of the following EXCEPT what against
the Light List? |
Rhythm |
Color |
Period |
Intensity |
When using a buoy as an aid to navigation which of the following should
be considered?
|
The
buoy should be considered to be in the charted position if it has been freshly
painted.
|
The
buoy should be considered to always be in the charted position.
|
If
the light is flashing the buoy should be considered to be in the charted
location.
|
The
buoy may not be in the charted position. |
When using a buoy as an aid to navigation which of the following should
be considered?
|
The
buoy may not be in the charted position.
|
If
the light is flashing, the buoy should be considered to be in the charted
location.
|
The
buoy should be considered to be in the charted position if it has been freshly
painted.
|
The
buoy should be considered to always be in the charted location. |
|
When should a navigator rely on the position of floating aids to navigation? |
During
daylight only |
Only
when inside a harbor |
During
calm weather only |
Only
when fixed aids are not available |
|
When navigating a vessel, you __________. |
can
always rely on a buoy to show proper light characteristics |
should
assume a wreck buoy is directly over the wreck |
should
never rely on a floating aid to maintain its exact position |
can
always rely on a buoy to be on station |
|
When you are steering on a pair of range lights and find the upper light
is in line above the lower light, you should __________. |
wait
until the lights are no longer in a vertical line |
continue
on the present course |
come
right |
come
left |
|
When you are steering on a pair of range lights and find the upper light
is in line above the lower light, you should __________. |
come
left |
come
right |
wait
until the lights are no longer in a vertical line |
continue
on the present course |
|
When you are steering on a pair of range lights and find the upper light
is above the lower light you should __________. |
come
left |
wait
until the lights are no longer in a vertical line |
continue
on the present course |
come
right |
|
When you are steering on a pair of range lights and find the upper light
is above the lower light you should __________. |
come
left |
wait
until the lights are no longer in a vertical line |
come
right |
continue
on the present course |
|
You are on course 226°T. In order to check the latitude of your vessel,
you should observe a celestial body on which bearing? |
270° |
026° |
000° |
226° |
|
You are on course 312°T. To check the speed of your vessel you should observe
a celestial body on which bearing? |
090° |
222° |
312° |
000° |
|
You are on course 238°T. To check the course of your vessel you should observe
a celestial body on which bearing? |
328° |
090° |
180° |
238° |
|
You are on course 303°T. To check the speed of your vessel you should observe
a celestial body on which bearing? |
090° |
000° |
213° |
123° |
|
You are on course 209°T. In order to check the longitude of your vessel,
you should observe a celestial body on which bearing? |
299° |
209° |
000° |
270° |
|
A line of position from a celestial observation is a segment of a __________. |
parallel
of declination |
parallel
of altitude |
circle
of equal altitude |
vertical
circle |
|
You are on course 042°T. To check the course of your vessel you should observe
a celestial body on which bearing? |
090° |
132° |
180° |
222° |
|
You are on course 146°T. To check the speed of your vessel you should observe
a celestial body on which bearing? |
000° |
056° |
090° |
146° |
|
You are on course 201°T. To check the speed of your vessel you should observe
a celestial body on which bearing? |
180° |
111° |
201° |
090° |
|
You are on course 061°T. To check the longitude of your vessel you should
observe a celestial body on which bearing? |
061° |
180° |
241° |
090° |
A latitude line will be obtained by observing a body __________.
|
on
the prime vertical
|
on
the celestial horizon
|
at
lower transit
|
on
the Greenwich meridian
|
|
While steering a course of 150°T, you wish to observe a body for a latitude
check. What would the azimuth have to be? |
090°T |
150°T |
000°T |
240°T |
|
While steering a course of 150°T, you wish to observe the Sun for a speed
check. What would the azimuth have to be? |
090°T |
150°T |
060°T |
240°T |
|
A star is observed at lower transit. The line of position derived from this
sight is __________. |
of
no special significance |
on
the prime vertical |
a
longitude line |
a
latitude line |
|
You are on course 138°T. To check the latitude of your vessel you should
observe a celestial body on which bearing? |
138° |
270° |
000° |
318° |
