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What will cause the ARPA to emit a visual alarm, audible alarm, or both?
An acquired target entering into a guard zone
A tracked target lost for one radar scan
A target being initially detected within a guard zone

A tracked target entering your preset CPA-TCPA limits
Your ARPA has been tracking a target and has generated the targets course and speed. The radar did not receive a target echo on its last two scans due to the weather. What should you expect under these circumstances?
The ARPA will generate data based on sea return echoes from the vicinity where the target was lost.
The ARPA will give an audible and/or visual lost target alarm.
The ARPA has lost all "memory" of the target and must recompute the target data.

The ARPA will generate data as if the target was still being tracked by radar.
Vessels required to have an Automatic Radar Plotting Aid must have a device to indicate the __________. ECDIS generated trackline vessel's position AIS information of vessels in the vicinity speed of the vessel over the ground or through the water
Vessels required to have an Automatic Radar Plotting Aid must have a device to indicate the __________. speed of the vessel over the ground or through the water distance to the next port time of the next navigational satellite pass None of the above
Your ARPA has automatic speed inputs from the log. Due to currents, the log is indicating a faster speed than the speed over the ground. What should you expect under these circumstances? The range of initial target acquisition will be less than normal. The generated CPA will be less than the actual CPA. The generated TCPA will be later than the actual TCPA. The targets true course vector will be in error.
Which ARPA data should you use in order to determine if a close quarters situation will develop with a target vessel? Set and drift of the current Initial range of acquisition Predicted time of CPA Relative track information
When using an ARPA, what should you consider in order to evaluate the information displayed? Navigational constraints may require a target vessel to change course. You cannot determine if a small target has been lost due to sea return. The trial maneuver feature will automatically determine a course that will clear all targets. The target vessel's generated course and speed are based solely on radar inputs.
The ARPA may swap targets when automatically tracking if two targets __________. are tracked on the same bearing pass close together are tracked on reciprocal bearings are tracked at the same range
Your ARPA has two guard zones. What is the purpose of the inner guard zone? Sound an alarm for targets first detected within the zone Alert the watch officer that a vessel is approaching the preset CPA limit Guard against target loss during critical maneuvering situations Warn of small targets that are initially detected closer than the outer guard zone
What is TRUE of the history display of a target's past positions on an ARPA? It provides a graphic display to emphasize which vessel is on a collision course.
In the true presentation, it provides a quick visual check to determine if a vessel has changed course.
 o
It provides a graphic display of a target vessel's relative course, speed, and CPA.
The display is one of the primary inputs and must be in use when using the trial maneuver capability.
When using the ARPA in heavy rain, which action should you take? Increase the STC setting to reduce close-in spurious signals. Increase the range of the inner and outer guard rings. Navigate as though the effective range of the radar has been reduced. Increase the radar gain to pick up weak echoes through the rain.
The typical operating range of automatic identification systems (AIS) at sea is nominally __________. 6-8 nm 50-75 nm 20-25 nm 3-4 nm
In general, on how many radio channels will an automatic identification system (AIS) operate? 2 4 6 8
An automatic identification system (AIS) transponder transmits and receives information broadcasts on __________? VHF maritime band 10 cm, S-band radar 3 cm, X-band radar UHF L-band
What does an automatic identification system (AIS) transponder use to transmit and receive information broadcasts? 161.975 Mhz and 162.025 Mhz 1575.42 Mhz and 1227.6 Mhz 2182 Khz and 2187.5 Khz 3000 Mhz and 9200 Mhz
With respect to automatic identification systems (AIS), which information is expected to be broadcast every 1 to 10 seconds? IMO number Vessel's draft Name of ship Ship's heading
With respect to automatic identification systems (AIS), which information is required to be broadcast every 1 to 10 seconds? Call sign and IMO number MMSI number and call sign Route Plan and navigational status Course over ground and MMSI
Automatic identification systems (AIS) are expected to broadcast all of the following information EXCEPT __________. ship's heading time stamp navigation status port of origin
While underway, a vessel over 100,000 gross tons with an automatic identification systems (AIS) is expected to broadcast all of the following information every 1 to 10 seconds EXCEPT __________. ship's heading navigational status rate of turn name of vessel
While underway, automatic identification systems (AIS) broadcast all of the following information every 1 to 10 seconds EXCEPT the __________. latitude and longitude ship's scantlings speed over ground course over ground
Which information must automatic identification systems (AIS) automatically provide to appropriately equipped shore stations, vessels and aircraft? Vessel's type Vessel's course Navigational status All of the above.
With respect to automatic identification systems (AIS) which of the following information is broadcast every one to ten seconds? Vessel's draft Dimensions of vessel Air Draft Navigational status
With respect to automatic identification systems (AIS), which information is required to be broadcast every 1 to 10 seconds? Vessel's draft Call sign Route plan None of the above
With respect to automatic identification systems (AIS), which information is expected to be broadcast every 1 to 10 seconds? Latitude and longitude Navigational status Rate of turn All of the above.
With respect to automatic identification systems (AIS), which information is required to be broadcast every 1 to 10 seconds? Destination Location of antenna Time stamp None of the above
Automatic identification systems (AIS) are required to __________. receive safety-related information automatically from similarly equipped vessels exchange safety-related information with shore-based facilities provide safety-related information automatically to shore stations, other vessels and aircraft All of the above.
The short text messaging feature of the automatic identification system (AIS) allows for messages of up to __________.
56 characters
64 characters
128 characters

158 characters
Which of the following statements is TRUE regarding automatic identification systems (AIS)?
AIS is a short-range 3 cm X-band radar system that automatically sends a vessel's position, course, speed and other safety related information to all those with similar equipment within the area.
AIS is a global tracking system that relies upon INMARSAT C service to communicate vessel position, course, speed and other safety related information to all those with similar equipment in the area.
AIS is a one-way centrally managed system that requires the local VTS to send commands to instruct each vessel to broadcast position, course, speed and other safety related information to all those with similar equipment in the area.

AIS is a short-range VHF-FM system that automatically broadcasts a vessel's position, course, speed and other safety related information to all those with similar equipment in the area.
Which of the following statements is TRUE regarding automatic identification systems (AIS)?
AIS is designed to replace ARPA, maneuvering boards, and visual bearings as a means to ascertain the risk of collision.
AIS will not provide information on another vessel if that vessel is indistinguishable in radar sea clutter.

AIS provides near real-time information regarding another vessel's speed over ground and heading regardless of visibility. AIS can be relied upon as the sole means to determine course changes due to other AIS equipped traffic.
Which of the following statements is TRUE regarding automatic identification systems (AIS)?
AIS provides the other vessel's identity, dimensions and navigational status regardless of visibility.
AIS will not provide information on another vessel if that vessel is indistinguishable in radar sea clutter.
AIS can be relied upon as the sole means to determine risk of collision and safe speed.
AIS is designed to replace ARPA, maneuvering boards, and visual bearings as a means to ascertain the risk of collision.
Which of the following statements is TRUE regarding automatic identification systems (AIS)?
AIS cannot be used to make passing arrangements because the system is not capable of this type of ship-to-ship communications.
AIS can be used to make passing arrangements via ship-to-ship text massaging thus relieving a vessel operator from making such arrangements via bridge-to-bridge radiotelephone or signaling intent to pass via whistle signals.
AIS cannot be used to make passing arrangements because the ship-to-ship text messaging feature is for emergency use only.

AIS can be used to make passing arrangements via ship-to-ship text messaging but a vessel operator is not relieved from the requirement to sound whistle signals or make arrangements via bridge-to-bridge radiotelephone.
Which of the following statements is TRUE regarding automatic identification systems (AIS)? Under no circumstances shall AIS be turned off while underway as this could endanger the vessel and those around her.
The master may, at his/her discretion, turn off the AIS if he/she believes that it may compromise the safety or security of the vessel.
AIS is always required to be operating if the vessel is within 100 nautical miles of the coastline.
AIS is always required to be operating if the vessel is in or in the vicinity of a VTS area.
Time signals broadcast by WWV and WWVH are transmitted __________. every 15 minutes every 30 minutes continuously throughout day every hour
Yesterday you took a time tick using the 1200 GMT broadcast, and the chronometer read 11h 59m 59s. Today at the 1200 GMT time tick the chronometer read 00h 00m 01s. What is the chronometer error? Losing 2 seconds Gaining 2 seconds Fast 1 second Fast 2 seconds
Yesterday your chronometer read 03h 01m 56s at the 1500 GMT time tick. Today your chronometer read 03h 01m 54s at the 1500 GMT time tick. What is the chronometer rate? +2s 2s fast -2s 1m 54s fast
Yesterday your chronometer read 11h 59m 59s at the 1200 GMT time tick. Today the chronometer reads 11h 59m 57s at the 1200 time tick. What is the chronometer rate? -3s +2s -2s +3s
Yesterday your chronometer read 11h 59m 58s at the 1200 GMT time tick. Today your chronometer reads 12h 00m 00s at the 1200 time tick. What is the chronometer rate?
Nil
12h
-2s

+2s
Yesterday your chronometer read 03h 01m 56s at the 1500 GMT time tick. Today your chronometer read 03h 01m 58s at the 1500 GMT time tick. What is the chronometer error? 01m 58s fast 03h 01m 58s fast +2s -2s
Yesterday your chronometer read 02h 59m 58s at the 1500 GMT time tick. Today the chronometer reads 03h 00m 02s at the 1500 GMT time tick. What is the chronometer error? 03h 00m 02s fast +3s -3s 02s fast
Chronometer error may be found by __________.
radio time signal
applying the prevailing chronometer rate to previous readings
comparison with a timepiece of known error

All of the above.
A marine chronometer should be rewound once every __________. 12 hours day 3 days week
When using a mechanical (windup type) marine chronometer, how often should it be reset? Whenever the chronometer error exceeds approximately four minutes At the start of each voyage If the chronometer rate changes from gaining to losing or vice versa Only when it is overhauled
Yesterday your chronometer read 11h 59m 59s at 1200 GMT time tick. Today the chronometer reads 12h 00m 01s at the 1200 GMT tick. What is the chronometer rate?
-1s
+1s
-2s

+2s
Quadrantal error in a gyrocompass has its GREATEST effect on which of the following in high latitudes
on intercardinal headings near the equator on north or south headings
What is the gyrocompass error resulting from your vessel's movement in OTHER than an east-west direction? damping error ballistic deflection

speed erro quadrantal error
If the gyrocompass error is east, what describes the error and the correction to be made to gyrocompass headings to obtain true headings? The readings are too high (large numerically) and the amount of the error must be added to the compass to obtain true
The readings are too low (small numerically) and the amount of the error must be added to the compass to obtain true The readings are too high and the amount of the error must be subtracted from the compass to obtain true The readings are too low and the amount of the error must be subtracted from the compass to obtain true
Which statement about gyrocompass error is TRUE?
The amount of the error and the sign will generally be the same on all headings. The sign (E or W) of the error will change with different headings of the ship. Any error shown by a gyro repeater will be the same as the error of the master compass. Any error will remain constant unless the compass is stopped and restarted.
Which of the following is the most accurate method of determining gyrocompass error while underway determining from the chart the course made good between celestial fixes
comparing the gyro azimuth of a celestial body with the computed azimuth of the body comparing the gyro heading with the magnetic compass heading It cannot be determined accurately at sea due to drift of unknown currents.
How can the accuracy of an azimuth circle be checked? sighting a terrestrial range in line and comparing the observed bearing against the charted bearing
comparing observed azimuths at different altitudes with computed values at the times of observation to see if the difference is constant
aligning the relative bearing markings so that 000 is on the lubber's line and the line of sight passes over the center of the compass
ensuring that the alignment marks on the inner face of the circle are in line with those on the repeater on relative bearings of 000 and 090
The reaction of a gyrocompass to an applied force is known as __________. gravity effect gyroscopic inertia earth rate

precession
The spin axis of a gyroscope tends to remain fixed in space in the direction in which it is started. How does this gyroscope become north seeking so that it can be used as a compass?
By mechanically or electrically applying forces to precess the gyroscope By taking advantage of the property of gyroscopic inertia By starting the compass with the spin axis in a north/south position The rotation of the Earth (Earth rate) automatically aligns the gyroscope with north, except for speed errors
The directive force of a gyrocompass __________. increases with latitude, being maximum at the geographic poles remains the same at all latitudes

decreases with latitude, being maximum at the geographic equator is greatest when a vessel is near the Earth's magnetic equator
Which statement about the gyrocompass is FALSE? It can be used near the Earth's magnetic poles. It seeks the true meridian.

Its accuracy remains the same at all latitudes If an error exists, it is the same on all headings.
A system of reservoirs and connecting tubes in a gyro compass is called a __________. spider element mercury ballistic gyrotron rotor
At the master gyrocompass, the compass card is attached to the __________. pickup transformer sensitive element link arm spider element
Indications of the master gyrocompass are sent to remote repeaters by the __________. follow-up system transmitter phantom element azimuth motor
Gyrocompass repeaters reproduce the indications of the master gyrocompass. They are __________. hand operated accurate electronic servomechanisms accurate only in the Polar regions accurate only if the vessel is underway
Compass deviation is caused by __________. a dirty compass housing misalignment of the compass magnetism within the vessel magnetism from the earth's magnetic field
Compass error is equal to the __________. difference between true and magnetic heading combined variation and deviation deviation minus variation variation plus compass course
Error may be introduced into a magnetic compass by __________. belt buckles making a structural change to the vessel a short circuit near the compass All of the above.
The quadrantal spheres are used to __________. remove deviation on the intercardinal headings remove heeling error compensate for induced magnetism in vertical soft iron remove deviation on the cardinal compass headings
The purpose of the soft iron spheres mounted on arms on the binnacle is to compensate for __________. the residual deviation the vertical component of the permanent magnetism of the vessel magnetic fields caused by electrical currents in the vicinity induced magnetism in the horizontal soft iron
Variation is the angular measurement between __________. your vessel's heading and the magnetic meridian compass north and true north magnetic meridian and the geographic meridian compass north and magnetic north
Which compensates for induced magnetism in the horizontal soft iron of a vessel? Magnets in trays inside the binnacle A single vertical magnet under the compass The Flinders bar Iron spheres mounted on the binnacle
True heading differs from magnetic heading by __________. deviation compass error variation northerly error
The vertical component of the Earth's magnetic field causes induced magnetism in vertical soft iron. This changes with latitude. What corrects for this coefficient of the deviation? The Flinders bar Bar magnets in the binnacle Quadrantal soft iron spheres The heeling magnet
The difference in degrees between true north and magnetic north is called __________. drift compass error variation deviation
To find a magnetic compass course from a true course you must apply __________. deviation and variation variation magnetic anomalies (local disturbances) deviation
The Flinders bar on a magnetic compass compensates for the __________. induced magnetism in horizontal soft iron vessel's inclination from the vertical permanent magnetism in ship's steel induced magnetism in vertical soft iron
Which statement about the Flinders bar of the magnetic compass is CORRECT? It compensates for quadrantal deviation. It is only needed in equatorial waters. It compensates for error caused by the heeling of a vessel. It compensates for the error caused by the vertical component of the Earth's magnetic field.
A single vertical magnet placed underneath the compass in the binnacle is used to compensate for __________. induced magnetism in the vertical soft iron deviation caused by the vessel's inclination from the vertical induced magnetism in the horizontal soft iron the horizontal component of the permanent magnetism
The principal purpose of magnetic compass adjustment is to __________.
reduce the variation as much as possible
allow the compass bowl to swing freely on its gimbals
reduce the magnetic dip as much as possible

reduce the deviation as much as possible
When adjusting a magnetic compass for error, a deviation table should be made __________. after adjusting the fore-and-aft and athwartships permanent magnets before the quadrantal correctors are placed on the compass before correcting for any deviation after correcting for variation
Deviation which is maximum on intercardinal compass headings may be removed by the __________. soft iron spheres on the sides of the compass fore-and-aft magnets transverse magnets Flinders bar
Before a magnetic compass is adjusted certain correctors must be checked to ensure that they are free of permanent magnetism. These correctors are the __________. fore-and-aft and athwartships magnets Flinders bar and quadrantal spheres dip needle and heeling magnet heeling magnet and Flinders bar
The Flinders bar and the quadrantal spheres should be tested for permanent magnetism at what interval? Semiannually They are not subject to permanent magnetism; no check is necessary. Every five years Annually
The total magnetic effects which cause deviation of a vessel's compass can be broken down into a series of components which are referred to as __________. equations fractional parts coefficients divisional parts
Magnetic compass deviation __________. is the angular difference between magnetic north and compass north is the angular difference between geographic and magnetic meridians is published on the compass rose on most nautical charts varies depending upon the bearing used
If a ship is proceeding towards the magnetic equator, the uncorrected deviation due to permanent magnetism __________. remains the same
is unimportant and may be neglected

decreases increases
If a ship is proceeding towards the magnetic equator, which is TRUE concerning the uncorrected deviation due to permanent magnetism?
The deviation will increase It is unimportant and may be neglected The deviation will decrease It remains the same
If the compass heading and the magnetic heading are the same then __________. there is something wrong with the compass the deviation has been offset by the variation there is no deviation on that heading the compass is being influenced by nearby metals
If the magnetic heading is greater than the compass heading, the deviation is __________. north west south east
The difference between magnetic heading and compass heading is called __________. compass error drift variation deviation
Deviation is the angle between the __________. axis of the compass card and the degaussing meridian true meridian and the axis of the compass card true meridian and the magnetic meridian magnetic meridian and the axis of the compass card
The horizontal angle between the magnetic meridian and the north-south line of the magnetic compass is __________. deviation compass error dip variation
The compass deviation changes as the vessel changes __________. speed longitude heading geographical position
Deviation is caused by __________. magnetic influence inherent to that particular vessel changes in the earth's magnetic field nearby magnetic land masses or mineral deposits the magnetic lines of force not coinciding with the lines of longitude
Deviation in a compass is caused by the __________. influence of the magnetic materials of the vessel vessel's geographic position vessel's heading earth's magnetic field
Variation in a compass is caused by __________. lack of oil in the compass bearings magnetism within the vessel magnetism from the earth's magnetic field worn gears in the compass housing
Magnetic variation changes with a change in __________. seasons sea conditions the vessel's position the vessel's heading
Variation is not constant; it is different with every change in __________. cargo speed vessel heading geographical location
If a magnetic compass is not affected by any magnetic field other than the Earth's, which statement is TRUE? There will be no compass error. Compass error and variation are equal. Compass north will be true north. Variation will equal deviation.
The compass error of a magnetic compass that has no deviation is __________. equal to variation zero eliminated by adjusting the compass constant at any geographical location
When crossing the magnetic equator the __________. Flinders bar should be inverted Flinders bar should be moved to the opposite side of the binnacle the quadrantal spheres should be rotated 180 heeling magnet should be inverted
What are the only magnetic compass correctors that correct for both permanent and induced effects of magnetism? Quadrantal spheres Athwartships magnets Fore-and-aft magnets Heeling magnets
Which compensates for errors introduced when the vessel heels over? A single vertical magnet beneath the compass The soft iron spheres on the arms of the binnacle Magnets placed in trays inside the binnacle The Flinders bar
Heeling error is defined as the change of deviation for a heel of __________. 1While the vessel is on a compass heading of 000 2 and is constant on all headings 1 while the vessel is on a compass heading of 180 2While the vessel is on an intercardinal heading
The standard magnetic compass heading differs from the true heading by __________. variation latitude deviation compass error
When changing from a compass course to a true course you should apply __________. deviation variation and deviation variation a correction for the direction of current set
The chart indicates the variation was 345'W in 1988, and the annual change is decreasing 6'. If you use the chart in 1991 how much variation should you apply? 327'W 327'E 403'W 403'E
The chart indicates the variation was 345'W in 1988, and the annual change is increasing 6'. If you use the chart in 1991 how much variation should you apply? 327'W 327'E 403'W 403'E
The chart indicates the variation was 345'E in 1988, and the annual change is increasing 6'. If you use the chart in 1991 how much variation should you apply? 327'E 327'W 345'E 403'E
Variation is a compass error that you __________. can correct by adjusting the compass card cannot correct can correct by adjusting the compensating magnets can correct by changing the vessel's heading
Error may be introduced into a magnetic compass by __________. making a structural change to the vessel a short circuit near the compass belt buckles All of the above.
The lubber's line on a magnetic compass indicates __________. the direction of the vessel's head magnetic north a relative bearing taken with an azimuth circle compass north
The MOST important feature of the material used for making the binnacle of a standard magnetic compass is that it is __________. corrosion resistant weatherproof capable of being permanently affixed to the vessel nonmagnetic
Which would influence a magnetic compass? Electrical wiring Iron pipe Radio All of the above.
As a vessel changes course to starboard, the compass card in a magnetic compass __________. also turns to starboard remains aligned with compass north turns counterclockwise to port first turns to starboard then counterclockwise to port
The permanent magnetism of a vessel may change in polarity due to __________. being moored on a constant heading for a long period of time a collision with another vessel being struck by lightning All of the above.
Which would influence a magnetic compass? Radio Iron pipe Electrical wiring All of the above.
How can the permanent magnetism of a vessel change in strength?
Welding and major structural repair The nature of the cargo being carried Changes in the vessel's heading Geographical location of vessel
The lubber's line on a magnetic compass indicates __________. compass north the direction of the vessel's head magnetic north a relative bearing taken with azimuth circle
The permanent magnetism of a vessel may change in polarity due to __________. the nature of the cargo being carried changes in heading major structural repair All of the above.
The permanent magnetism of a vessel may change in polarity due to __________. being struck by lighting steaming from the north magnetic hemisphere to the south magnetic hemisphere being moored for a long time on one heading loading a homogenous magnetic cargo such as steel plate, iron bars, etc.
Magnets are placed in horizontal trays in the compass binnacle to compensate for the __________. magnetic fields caused by electrical currents in the vicinity induced magnetism in the vessel's horizontal soft iron change in the magnetic field when the vessel inclines from vertical permanent magnetism of the vessel
Magnets in the binnacles of magnetic compasses are used to reduce the effect of __________. variation deviation local attraction All of the above.
Permanent magnetism is caused by __________. the horizontal component of the earth's magnetic field acting on the horizontal soft iron the vertical component of the earth's magnetic field acting on the vertical soft iron the earth's magnetic field affecting the ship's hard iron during construction operation of electrical equipment and generators on board ship
At the magnetic equator there is no induced magnetism in the vertical soft iron because __________. the lines of force cross the equator on a 0-180 alignment the quadrantal error is 0 there is no vertical component of the Earth's magnetic field the intercardinal headings have less than 1 error
The greatest directive force is exerted on the magnetic compass when the __________. needles are nearly in line with the meridian vessel is near the magnetic poles vessel is near the magnetic equator variation is near zero
The magnetic compass magnets are acted on by the horizontal component of the Earth's total magnetic force. This magnetic force is GREATEST at the __________. south magnetic pole north magnetic pole magnetic prime vertical meridian magnetic equator
Magnetism which is present only when the material is under the influence of an external field is called __________. residual magnetism permanent magnetism induced magnetism terrestrial magnetism
Induced magnetism is found in __________. hard iron horizontal iron only vertical iron only soft iron
The line which connects the points of zero magnetic dip is __________. an agonic line the magnetic equator a magnetic meridian All of the above.
The line connecting the points of the earth's surface where there is no dip is the __________. isopor agonic line isodynamic magnetic equator
The points on the earth's surface where the magnetic dip is 90 are __________ along the magnetic equator
the magnetic poles the isopors connected by the isoclinal line
The vertical angle between the horizontal and the magnetic line of force is the __________.
dip magnetic angle vertical angle elevation
Magnetic dip is a measurement of the angle between the __________ geographic pole and the magnetic pole
horizontal and the magnetic line of force lubber's line and true north compass heading and the magnetic heading
What is the basic principle of the magnetic compass? The Earth's magnetic lines of force are parallel to the surface of the Earth. The compass needle(s) will, when properly compensated, lie parallel to the isogonic lines of the Earth.

Magnetic materials of the same polarity repel each other and those of opposite polarity attract Magnetic meridians connect points of equal magnetic variation.
By convention, the Earth's north magnetic pole is colored __________. black red

blue white
By convention, the south pole of a magnet is painted __________. red black white blue
By convention, the north pole of a magnet is painted __________. red blue white black
By convention, the Earth's north magnetic pole is colored __________. black red blue white
By convention, the south seeking ends of a compass' magnets are colored __________. white black blue red
By convention, the north seeking ends of a compass' magnets are colored __________. black red blue white
What is an advantage of the magnetic compass aboard vessels? It does not have to be checked as often. Compass error is negligible at or near the earth's magnetic poles. All points on the compass rose are readily visible. It is reliable due to it's essential simplicity.
When a magnetic compass is not in use for a prolonged period of time it should __________. be locked into a constant heading have any air bubbles replaced with nitrogen be shielded from direct sunlight have the compensating magnets removed
A magnetic compass card is marked in how many degrees? 90 180 360 400
When a magnetic compass is not in use for a prolonged period of time it should __________. have the compensating magnets removed be shielded from direct sunlight have any air bubbles replaced with nitrogen be locked into a constant heading
A magnetic compass card is marked in how many degrees? 90 180 360 400
The heading of a vessel is indicated by what part of the compass? Gimbals Card Lubber's line Needle
How many degrees are there on a compass card? 360 380 390 420
What is the compass course of a vessel heading NNW? 274.5 292.0 315.5 337.5
What is the compass course of a vessel heading NW? 274.5 292.5 315.0 337.5
What is the compass course of a vessel heading SSW? 202.5 225.0 247.5 270.0
What is the compass course of a vessel heading SW? 202.5 225.0 247.5 270.0
What is the compass course of a vessel heading WSW? 202.5 225.0 247.5 271.0
What is the compass course of a vessel heading WNW? 270.0 292.5 315.0 337.5
What is the compass course of a vessel heading SSE? 112.5 135.0 157.5 180.0
What is the compass course of a vessel heading SE? 112.5 135.0 157.5 180.0
What is the compass course of a vessel heading ESE? 112.5 135.0 157.5 180.0
What is the compass course of a vessel heading ENE? 022.5 045.0 067.5 090.0
What is the compass course of a vessel heading NE? 022.5 045.0 067.5 090.0
What is the compass course of a vessel heading NNE?
022.5
045.0
067.5
090.0
Which of the following is a compass card without north-seeking capability that is used for relative bearings? alidade bearing bar bearing circle pelorus
Eight points of a compass are equal to how many degrees? 45 90 180 360
One point of a compass is equal to how many degrees? 7.5 11.25 17.5 22.5
How many points are there in a compass card? 4 8 24 32
The heading of a vessel is indicated by what part of the compass? Lubber's line Card Needle Gimbals
A vessel heading NNW is on a course of __________. 274.5 292.0 315.5 337.5
A vessel heading NW is on a course of __________. 274.5 315.0 337.5 292.5
A vessel heading NE is on a course of __________. 022.5 045.0 067.5 090.0
A vessel heading SSW is on a course of __________. 202.5 225.0 247.5 270.0
A vessel heading WSW is on a course of __________. 202.5 225.0 247.5 271.0
A vessel heading SSE is on a course of __________. 112.5 135.0 157.5 180.0
A vessel heading ESE is on a course of __________. 112.5 135.0 157.5 180.0
A vessel heading NNE is on a course of __________. 022.5 045.0 067.5 090.0
A vessel heading SW is on a course of __________. 202.5 225.0 247.5 270.0
A vessel heading WNW is on a course of __________. 270.0 292.5 315.0 337.5
A vessel heading SE is on a course of __________. 112.5 180.0 135.0 157.5
A vessel heading ENE is on a course of __________. 022.5 045.0

067.5 090.0
A Doppler log in the volume reverberation mode indicates __________. speed through the water speed being made good the set of the current the depth of the water
A Doppler speed log indicates speed through the water __________. at all times only when there is no current in the bottom return mode in the volume reverberation mode
A Doppler speed log indicates speed over ground __________. in the bottom return mode in the volume reverberation mode only when there is no current at all times
A Doppler log in the bottom return mode indicates the __________. bottom characteristics speed over the ground velocity of the current depth of the water
What will NOT induce errors into a Doppler sonar log? Roll Increased draft Change in trim Pitch
You have replaced the chart paper in the course recorder. What is NOT required to ensure that a correct trace is recorded? Adjust the chart paper to indicate the correct time Set the zone pen on the correct quadrant Test the electrical gain to the thermograph pens Line the course pen up on the exact heading of the ship
If the electronic chart is part of an ECDIS, it must display the minimum data required by IMO/IHO, to include all of the following EXCEPT __________. hydrography aids to navigation regulatory boundaries tidal currents
Which of the following must the electronic chart of an ECDIS display, as required by IMO/IHO? Hydrography Regulatory boundaries Ferry routes All of the above.
ECDIS units incorporate Digital Chart Data Formats, which include __________. vector and raster raster only vector only imposed viewing
Raster-scan chart data is __________. a digitized "picture" of a chart in one format and one layer the only format recognized by IMO/IHO organized into many separate files composed of files that are smaller than vector files
Which of the following are data layer categories to be displayed on ECDIS? ECDIS warnings and messages Notice to Mariners information Hydrographic Office data All of the above.
Which of the following data layer categories is NOT displayed on ECDIS? Hydrographic Office data ECDIS warnings and messages Notice to Mariners information Ship hydrodynamic information
An ECDIS is required to display which information?

Hydrographic data

ARPA vectors

Radar targets

All of the above.
An ECDIS is required to display which information? Meteorological data Soundings Waypoints Radar targets
An ECDIS is required to display which information? Speed of advance
Climatology data

Depth contours Water temperature
The database resulting from (1) the transformation of the electronic navigational chart (ENC) by ECDIS for appropriate use, (2) the updates to the ENC by appropriate means, and (3) the additional data added by the mariner, is called the __________. display base information chart display information standard display information system electronic navigational chart
The database information that should be shown when a chart is first displayed on ECDIS is the __________. chart display information

standard display information

display base information

system electronic nautical chart
The level of database information which cannot be removed from the ECDIS display and consists of information which is required at all times in all geographic areas and under all circumstances is the __________. system electronic nautical chart chart display information standard display information display base information
Chart information details to be used in ECDIS should be the latest edition of information originated by a government-authorized hydrographic office and conform to the standards of (the) __________. NASA International Maritime Organization US Coast Guard International Hydrographic Organization
ECDIS must give an alarm for which of the following cases? If the ship, within a specified time set by the watch officer, is going to cross the boundary of a prohibited area When the specified limit for deviation from the planned route is exceeded If the ship, within a specified time set by the watch officer, is going to cross a safety contour All of the above.
ECDIS must give an alarm for which of the following cases? If the ship is going to reach a critical point on the planned route When the speed of a dangerous target exceeds a set limit If the ship's ETA has changed beyond the set limit All of the above.
ECDIS must give an alarm for which of the following cases? When the speed of a dangerous target exceeds a set limit When the specified limit for deviation from the planned route is exceeded If the ship's ETA has changed beyond the set limit None of the above
ECDIS must have the capability to preserve the record of the voyage track for the previous __________. 4 hours 6 hours 12 hours 24 hours
Which data must ECDIS be able to record at one-minute intervals?
Position Course made good history Electronic navigational chart source All of the above.
Which data must ECDIS be able to record at one-minute intervals? Course made good history Speed through the water Estimated time of arrival Shaft RPM
Which of the following must an ECDIS system be able to perform? Conversion of "graphical coordinates" to "display coordinates" Transformation of local datum to WGS-'84 datum Calculation of true azimuth and distance between two geographical points All of the above.
ECDIS must be able to perform all of the following EXCEPT __________. determine magnetic compass deviation convert "graphical coordinates" to "display coordinates" determine true bearing and distance between two geographical points transform a local datum to the WGS-'84 datum
What will cause the Electronic Plotting Aid (EPA) to emit a visual alarm, audible alarm, or both? A tracked target entering your preset CPA-TCPA limits A target being initially detected within a guard zone A tracked target lost for one radar scan An acquired target entering into a guard zone
An Electronic Plotting Aid (EPA) will drop off a target's vector if more than __________ minutes elapse between each manual plot.  3
2
6

10
What option does an Electronic Plotting Aid (EPA) not have? Trial Maneuver Preset CPA/TCPA Dual VRMs/EBLs Target Trails
Vessel required to have an Electronic Plotting Aid (EPA) must have a device to indicate the __________. speed of the vessel over the ground or through the water vessel's position depth of the water relative heading
How many targets can an Electronic Plotting Aid (EPA) track at the same time? 2
20
5
10
Your Electronic Plotting Aid (EPA) has automatic speed inputs from the log. Due to currents, the log is indicating a faster speed than the speed over the ground. What should you expect under these circumstances? The targets true course vector will be in error. The generated CPA will be less than the actual CPA. The range of initial target acquisition will be less than normal. The generated TCPA will be later than the actual TCPA.
Which Electronic Plotting Aid (EPA) data should you use in order to determine if a close quarters situation will develop with a target vessel? Predicted time of the closest point of approach (CPA) Initial range of acquisition Vessel's true vector indicates vessel will cross your heading Relative track information
When using an Electronic Plotting Aid (EPA), what should you consider in order to evaluate the information displayed? Navigational constraints may require a target vessel to change course. The trial maneuver feature will automatically determine a course that will clear all targets. The target vessel's generated course and speed are based solely on radar inputs. You cannot determine if a small target has been lost due to sea return.
Your Electronic Plotting Aid (EPA) has two guard zones. What is the purpose of the inner guard zone? Alert the watch officer that a vessel is approaching the preset CPA limit Warn of small targets that are initially detected closer than the outer guard zone Sound an alarm for targets first detected within the zone Guard against target loss during critical maneuvering situations
Electronic Plotting Aid (EPA) has which built in functions? Plots at least 10 targets at one time Time of closest point of approach (TCPA) Target trails All of the above.
Electronic Plotting Aid (EPA) has which built in functions? Target CPA and time of CPA (TCPA) Trial maneuvering Automatic target tracking Plots at least 20 targets simultaneously
When using the Electronic Plotting Aid (EPA) in heavy rain, which action should you take? Navigate as though the effective range of the radar has been reduced. Increase the STC setting to reduce close-in spurious signals. Increase the radar gain to pick up weak echoes through the rain. Increase the range of the inner and outer guard rings.
The speed of sound through ocean water is nearly always __________. faster than the speed of calibration for the fathometer, unless the water is very warm faster than the speed of calibration for the fathometer the same speed as the speed of calibration for the fathometer slower than the speed of calibration for the fathometer
When operated over a muddy bottom, a fathometer may indicate __________. a zero depth reading a shallow depth reading no depth reading two depth readings
Which factor has the greatest effect on the amount of gain required to obtain a fathometer reading? Type of bottom Salinity of water Atmospheric pressure Temperature of water
The speed of sound in water is approximately __________. 1.5 times its speed in air 2.5 times its speed in air 3.5 times its speed in air 4.5 times its speed in air
When using an echo sounder in deep water, it is NOT unusual to __________.
have to recalibrate every couple of days due to inaccurate readings
receive false echoes at a constant depth day and night

receive a strong return at about 200 fathoms (366 meters) during the day, and one nearer the surface at night receive a first return near the surface during the day, and a strong return at about 200 fathoms (366 meters) at night
If a sound signal is emitted from the oscillator of a fathometer, and two seconds elapse before the returning signal is picked up, what depth of water is indicated? 824 fathoms 1048 fathoms 1248 fathoms 1648 fathoms
When using a recording depth finder in the open ocean, what phenomena is most likely to produce a continuous trace that may not be from the actual ocean bottom? Poor placement of the transducer on the hull Multiple returns reflected from the bottom to the surface and to the bottom again Echoes from schools of fish Echoes from a deep scattering layer
What should you apply to a fathometer reading to determine the depth of water? Add the draft of the vessel. Subtract the sea water correction. Subtract the draft of the vessel. Add the sea water correction.
All echo-sounders can measure the __________. average depth from waterline to hard bottom actual depth of water below keel average depth of water to soft bottom actual depth of water
An electronic depth finder operates on the principle that __________. radio signals reflect from a solid surface pressure increases with depth sound waves travel at a constant speed through water radar signals travel at a constant speed through water
The recording fathometer produces a graphic record of the __________. depth underneath the keel against a time base depth of water against a distance base contour of the bottom against a distance base bottom contour only up to depths of 100 fathoms
In modern fathometers the sonic or ultrasonic sound waves are produced electrically by means of a(n) __________. transmitter transducer amplifier transceiver
When using GPS without Selective Availability, you may expect your horizontal accuracy to be better than __________. 3 meters 20 meters 100 meters 200 meters
When navigating using GPS, what is an indicator of the geometry of the satellites that your receiver is locked onto? Selective Availability Precision Coding Doppler Shifting Horizontal Dilution of Precision
When using GPS, how many theoretical position lines are required for a two-dimensional fix?
1
2

3 4
Which theoretical minimum number of measurements from satellites does a GPS receiver need in order to provide an exact three-dimensional position? Five Four Three Two
With regard to GPS, a civilian receiver may be capable of achieving the same accuracy as a military receiver if __________. the horizontal dilution of precision is high the satellites are all below 15 in elevation your vessel is equipped with a Doppler receiver selective availability is set to zero
Which feature, when set to zero, might allow a GPS unit to have an accuracy equivalent to Precise Positioning Service receiver capability? Selective Availability Anti-spoofing Auto-correlation
 
Transit
The highest level of commercial navigational accuracy is provided by __________. NAVSAT, using the Doppler-shift DGPS, within a coverage area PPS, without selective availability SPS, without selective availability
A low HDOP (Horizontal Dilution of Precision) number such as 2 indicates a __________. poor signal quality good signal quality good fix poor fix
Which statement concerning GPS is TRUE? It cannot be used in all parts of the world. Two position lines are used to give a 2D fix. There are 12 functioning GPS satellites at present. It may be suspended without warning.
Most GPS receivers use the Doppler shift of the carrier phase to compute __________. Time Longitude Latitude Speed
Which type of GPS receiver has at least four channels to process information from several satellites simultaneously? Sequential Multiplex Continuous None of the above
What does not contribute to the commercial GPS receiver position error? Satellite clock Atmospheric/Ionospheric propagation Satellites' orbits Ship's speed
With respect to failure warnings and status indications, GPS receivers should provide, at a minimum, __________. an indication within 5 seconds if the specified HDOP has been exceeded a differential GPS status indication of the receipt of DGPS signals a warning of loss of position All of the above.
With respect to failure warnings and status indications, GPS receivers should provide, at a minimum, __________. a cross-track error alarm an indication of a change in satellite configuration an alarm if engine speed is suddenly reduced a warning of loss of position
A hand held instrument used to measure distances between objects and the ship is a __________. hygrometer vernier psychrometer stadimeter
Illustration D011NG below represents the geographic location of a vessel and the radar presentation at the same time. Which statement is TRUE? The small island is not detected due to the effect of beam width. Ship No. 2 is not detected due to the reflective mass of the background mountain overpowering the ship's reflective signals. Ship No. 1 is not detected due to the shadow effect of the headland. A tangent bearing of the headland to the south-southeast should be corrected by adding one-half of the beam width.
You are radar scanning for a buoy fitted with a racon. In illustration D017NG below, which radar screen represents the presentation you should expect on the PPI? A B C D
When using the radar for navigating __________.
the best fix is obtained by using a tangent bearing and a range
and using two radar ranges for a fix, the objects of the ranges should be close to reciprocal bearings
and crossing a radar range of one object with the visual bearing of a second object, the two objects should be 80 to 110 apart

and using ranges, the most rapidly changing range should be measured first
Illustration D011NG below represents the geographic location of a vessel and the radar presentation at the same time. Which statement is TRUE? A tangent bearing of the headland to the south-southeast is corrected by subtracting one-half of the beam width. Ship No. 2 is not detected due to the side lobe effect of radar reflecting from the mountain. Ship No. 1 does not appear as an individual target due to the effect of beam width. Small island is not detected due to the multiple echo effect from the mountain.
You are enroute to assist vessel A. Vessel A is underway at 6 knots on course 133T, and bears 042 at 105 miles from you. What is the course to steer at 10 knots to intercept vessel A? 063 068 073 079
You are approaching a light fitted with a RACON. The light may be identified on the radar by __________. a coded signal appearing on the same bearing at a greater range than the light a dashed line running from the center of the scope to the light an audible signal when the sweep crosses the light a circle appearing on the scope surrounding the light
You are enroute to assist vessel A. Vessel A is underway at 5 knots on course 063T, and bears 136T at 78 miles from you. What is the course to steer and running time at 13 knots to intercept vessel A? 158, 7h 20m 115, 7h 20m 158, 5h 45m 115, 5h 45m
You are enroute to assist vessel A. Vessel A is underway at 5.5 knots on course 033T, and bears 284T at 43 miles from you. What is the course to steer and running time at 16 knots to intercept vessel A? 265, 2h 32m 303, 3h 13m 265, 3h 13m 303, 2h 32m
You are approaching a sea buoy which emits a racon signal. This signal is most frequently triggered by which type of radar? 10 cm 3 cm Both 3 cm and 10 cm Signal does not depend on radar type.
In order to insure that the racon signal is visible on your 3 cm radar, the __________. rain clutter control should be off but, if necessary, may be on low gain control should be turned to maximum radar should be stabilized, head up 10 cm radar should be placed on standby or turned off
You are enroute to assist vessel A. Vessel A is underway at 4.5 knots on course 233T, and bears 264T at 68 miles from you. What is the course to steer and running time at 13 knots to intercept vessel A? 274, 7h 37m 254, 8h 35m 254, 7h 37m 274, 8h 35m
You are enroute to assist vessel A. Vessel A is underway at 4.5 knots on course 233T, and bears 346T at 68 miles from you. What is the course to steer at 13 knots to intercept vessel A? 323 314 327 318
You are enroute to assist vessel A. Vessel A is underway at 5.5 knots on course 033T, and bears 248T at 64 miles from you. What is the course to steer at 13 knots to intercept vessel A? 262 269 276 281
You are enroute to assist vessel A. Vessel A is underway at 6 knots on course 133T, and bears 343T at 92 miles from you. What is the course to steer at 9 knots to intercept vessel A? 356 022 038 003
You are enroute to assist vessel A. Vessel A is underway at 6 knots on course 133T, and bears 042T, 105 miles from you. What is the time to intercept if you make 10 knots? 12h 30m 12h 44m 12h 58m 13h 22m
You are enroute to assist vessel A. Vessel A is underway at 6 knots on course 133T, and bears 343T at 92 miles from you. What is the time to intercept if you make 9 knots? 6h 43m 6h 08m 7h 12m 7h 44m
You are enroute to assist vessel A. Vessel A is underway at 4.5 knots on course 233T, and bears 264T, 68 miles from you. What is the time to intercept if you make 13 Knots? 6h 31m 6h 47m 7h 03m 7h 37m
You are enroute to assist vessel A. Vessel A is underway at 5.5 knots on course 033T, and bears 248T at 64 miles from you. What is the time to intercept if you make 13 knots? 4h 36m 4h 55m 3h 59m 3h 44m
You are enroute to assist vessel A. Vessel A is underway at 5.5 knots on course 033T, and bears 284T, 43 miles from you. What is the time to intercept if you make 16 knots? 2h 16m 2h 22m 2h 32m 2h 42m
Coral atolls, or a chain of islands at right angles to the radar beam, may show as a long line rather than as individual targets due to __________. the multiple-target resolution factor the pulse length of the radar the effects of beam width limitations on range resolution
The signal from a ramark will show on the PPI as a __________. dashed circle at the same range as the transponder circle surrounding the transponder radial line from the transponder to the center of the PPI coded signal on the same bearing and at a greater range then the transponder
A radar display which is oriented, so that north is always at the top of the screen, is called a(n) __________. relative display stabilized display composite display unstabilized display
You are using a radar in which your own ship is shown at the center, and the heading flash always points to 0. If bearings are measured in relation to the flash, what type of bearings are produced? Compass Relative Magnetic TRUE
Your radar is set on a true motion display. Which of the following will appear to move across the PPI scope ? Echo from a ship at anchor Own ship's marker Echoes from land masses All of the above.
Your radar displays your ship off center. As you proceed on your course, your ship's marker moves on the PPI scope while echoes from land masses remain stationary. What is this display called? Off center True motion Head up
Stabilized
Your radar has a beam width of 2. The radar gyro bearing of the right tangent of an island is 316. The gyro error is 1E. Which true bearing should be plotted on the chart? 313 314 316 317
The beam width of your radar is 2. The left tangent bearing of a small island, as observed on the PPI scope, is 056pgc. If the gyro error is 2E, what bearing would you plot on the chart? 052 056 059 060
The radar control used to reduce sea return at close ranges is the __________. sensitivity time control pulse length control fast time constant gain control
When you turn on the fast time constant (differentiator) control of a radar it will __________. only suppress weak targets to a limited distance from the ship (sea clutter) reduce clutter over the entire PPI by shortening the echoes reduce the beam width to provide a map-like presentation for navigation enhance weak target echoes and brighten them on the PPI
The radar control that shortens all echoes on the display and reduces clutter caused by rain or snow is the __________. fast time constant (differentiator) sensitivity time control (sea clutter control) brilliance control receiver gain control
The radar control that reduces weak echoes out to a limited distance from the ship is the __________. sensitivity time control (sea-clutter control) fast time constant (differentiator) brilliance control receiver gain control
Radar makes the most accurate determination of the __________. distance to a target direction of a target size of a target shape of a target
What is the approximate wave length of an X Band Radar operating on a frequency of approximately 9500 MHz? 3 cm 10 cm 30 cm 100 cm
You have another ship overtaking you close aboard to starboard. You have 3 radar targets bearing 090 relative at ranges of .5 mile, 1 mile, and 1.5 miles. In this case, the unwanted echoes are called __________. side-lobe echoes indirect echoes multiple echoes spoking
An indirect radar echo is caused by a reflection of the main lobe of the radar beam off the observer's vessel. Which of the following is NOT a characteristic of indirect echoes? When plotted, their movements are usually abnormal. They always appear on a bearing of 90 from the true bearing of the contact. The indirect echoes usually appear in shadow sectors. Their bearing is almost constant, even when the true bearing of the contact changes appreciably.
Your radar indicates a target; however, there is no visible object at the point indicated. A large mountain, approximately 50 miles away on the same bearing as the target, is breaking the horizon. You should suspect the radar target is caused by __________. ducting sub-refraction ionospheric skip waves a submerged submarine
You have been observing your radar screen and notice that a contact on the screen has remained in the same position, relative to you, for several minutes. Your vessel is making 10 knots through the water. Which statement is TRUE? The contact is dead in the water. The radar is showing false echoes and is probably defective. The contact is on a reciprocal course at the same speed as your vessel. The contact is on the same course and speed as your vessel.
Which of the four adjustable errors in the sextant is the principle cause of index error? Telescope not being parallel to the frame
Index mirror and horizon glass not being parallel
Horizon glass not being perpendicular to the frame
Index mirror not being perpendicular to the frame
In what order should the following sextant adjustments be made?
{{{
I. Make telescope parallel to frame of sextant.
II. Set horizon glass perpendicular to frame of sextant.
III. Make index mirror and horizon glass parallel when index arm is set at zero.
IV. Set index mirror perpendicular to frame of sextant.}}}
III, II, IV, I IV, II, III, I I, II, III, IV I, IV, II, III
The part of a sextant mounted directly over the pivot of the index arm is the __________. micrometer drum index mirror horizon glass telescope
When the index and horizon mirrors of a properly adjusted sextant are at an angle of 45 to each other, the arc reads __________. 22 1/2 45 60 90
Which of the four adjustable errors in the sextant causes side error? Index mirror not being perpendicular to the frame Horizon glass not being perpendicular to the frame Elliptical centering error Telescope not being parallel to the frame
What causes the error of collimation with regards to the four adjustments to a sextant? Telescope not parallel to the frame The frame and horizon glass not perpendicular Personal error The frame and index mirror not perpendicular
The horizon glass of a sextant is __________. silvered on its half nearer the frame between the horizon and the shade glasses mounted on the index arm All of the above.
There are seven sources of error in the marine sextant. Of the four errors listed, which one is adjustable? Error of collimation Prismatic error Centering error Graduation error
Which is a nonadjustable error of the sextant? Error of perpendicularity Centering error Side error Error of collimation
Because of the reflecting properties of a sextant, if the sextant altitude reads 60 on the limb, the actual arc of the limb from 0 to the 60 reading is __________. 20 30 40 60
For a well made and well maintained sextant, the maximum value of which correction is usually so small that it can be ignored? Dip correction Instrument correction Personal correction Phase
A sextant having an index error that is "on the arc" has a __________.
semidiameter error
dip error
positive correction

negative correction
A sextant having an index error that is "off the arc" has a __________. dip error semidiameter error positive correction negative correction
The marine sextant is subject to seven different types of errors, four of which may be corrected by the navigator. An error NOT correctable by the navigator is __________. index error prismatic error perpendicularity of the horizon glass perpendicularity of the index mirror
What is a nonadjustable error of the sextant? Side error Prismatic error Error of collimation Index error
In order to remove index error from a sextant, you should adjust the __________. horizon glass to make it parallel to the sextant frame telescope to make it perpendicular to the sextant frame index mirror to make it parallel to the horizon glass with the index set at zero horizon glass to make it parallel to the index mirror with the index set at zero
Which of these sextant errors is nonadjustable? Prismatic error Centering error Graduation error All of the above.
Index error of a sextant is primarily caused by __________. improperly correcting the other errors in a sextant the horizon glass not being parallel to the horizon mirror the horizon glass not being parallel to the index mirror human error in taking a celestial observation
The index error is determined by adjusting the __________. horizon glass micrometer drum index mirror sextant frame
A marine sextant has the index arm set at zero and the reflected image of the horizon forms a continuous line with the actual image. When the sextant is rotated about the line of sight the images separate. The sextant has __________. prismatic error error of perpendicularity side error centering error
In order to remove side error from a sextant, you should adjust the __________. horizon glass to make it perpendicular to the sextant frame telescope to make it parallel to the sextant frame horizon glass to make it perpendicular to the index mirror with the index set at zero horizon glass to make it parallel to the horizon mirror with the index set at zero
While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 5.5 seconds after the signal was sounded. What is the distance to the shore? 3825 ft (1166 meters) 3072 ft (936 meters) 3450 ft (1052 meters) 2475 ft (754 meters)
You are approaching Chatham Strait from the south in foggy weather. You have Coronation Island and Hazy Islands on the radar. Suddenly the radar malfunctions. You then resort to using whistle echoes to determine your distance off Coronation Island. Your stopwatch reads 16.3 seconds for the echo to be heard. How far are you off Coronation Island? 1.0 mile 1.5 miles 2.0 miles 2.5 miles
While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 6 seconds after the signal was sounded. What is the distance to the shore? 1100 yards 1000 yards 900 yards 1200 yards
While navigating in fog off a coastline of steep cliffs, you hear the echo of the ship's fog horn 4 1/2 seconds after the signal was sounded. What is the distance to the shore? 405 yards 628 yards 730 yards 825 yards
While navigating in fog off a coastline of steep cliffs, you hear the echo of the ship's fog horn 4 seconds after the signal was sounded. What is the distance to the shore? 209 yards 363 yards 480 yards 730 yards
While navigating in fog off a coastline of steep cliffs, you hear the echo of the ship's fog horn 3 seconds after the signal was sounded. What is the distance to the shore? 872 yards 792 yards 550 yards 1100 yards
While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 2 1/2 seconds after the signal was sounded. What is the distance to the shore? 225 yards 460 yards 750 yards 910 yards
While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 2 seconds after the signal was sounded. What is the distance to the shore? 320 yards 140 yards 360 yards 280 yards
While navigating in fog off a coastline of steep cliffs, you hear the echo of the ships fog horn 3 1/2 seconds after the signal was sounded. What is the distance to the shore? 315 yards
640 yards
480 yards
143 yards