NAVIGATION 05

How does inclement weather effect RADAR/ARPA?

n ARPA acquisition, targets NOT detected in 5 consecutive scans become ______?

Which structures would NOT caused blind and shadow sectors to radar?

Which of the following is NOT stabilized?

Which ARPA display mode shows without azimuth stabilization in which the line connecting the center with the top of the display indicates own ship’s heading?

The position of own ship on such a display moves in accordance with it’s own motion is called_____.

After switching power on radar, you will have to wait until the set warms up for _______seconds.

Which of the following would NOT be considered an input to the computer of a collision avoidance system?

Which factor is NOT considered in establishing a safe CPA?

The length of a vector depends on the _________

Which name is associated with a tracked target which appears to have been temporarily lost or which has a poorly defined radar aspect, in so much that, the target does NOT have tracking ability?

A symbol that shows on the PPI scope a flashing triangle apex down, used to mark the target.

A symbol that shows a flashing diamond formed from two equal triangle, one apex up the other apex down.

A symbol that shows a flashing triangle apex up, used to mark the target.

Which of the following ARPA data should you use in order to determine if a close quarter situation will develop with a target vessel?

When using an ARPA, which of the following should you consider in order to evaluate the information displayed?

A navigator fixing a vessel’s position by radar ____.

Which term refers to the selection of targets that requires tracking procedure and the initiation of their tracking?

From the following remarks on Rule 8 of COLREGS 72 are mentioned correct EXCEPT:

When navigating in restricted visibility a power driven vessel shall _____.

As per COLREGS, in radar maneuvering it is better to make a 30 degrees course change in ____.

Which rule obligates the mariner to determine if a closed quarter’s situation is developing and/or risk of collision exists by radar plotting?

A technique used as a measure to monitor the progress of a vessel on the track and to minimize the cross-track distance.

The distance the vessel is to one side of the straight line between two waypoints.

ARPA is based on ___

Which ARPA display mode shows without azimuth stabilization in which the line connecting the center with the top of the display indicates ownship's heading?

The display on which ARPA information is presented should have an effective diameter of at least

It shows a square indicated by its corners centered around the target symbol.

Which of the following ARPA data should you use in order to determine if a close quarter situation will develop with vessel?

Vessels required to have an Automatic Radar Plotting Aid must have a device to indicate the ___

When will ARPA provide true data?

What is the purpose or function of the "Trial mode" used in most ARPA equipment?

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?

In for you observe your radar and determine that the risk. You should ____

You have been tracking a target and have generated the target 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?

What will cause the ARPA to emit a visual alarm, audible alarm, or both?

In ARPA, in what case you have lost target?

Your ARPA had two guard zones, what is the purpose of the inner guard zone?

When will ARPA emit an alarm to denote that a target is lost?

The recognition of the presence of a target is called __________

The closest point of approach of a contact on a relative motion radar may be determined

Comparing manual and automatic acquisition in ARPA, which is most sensitive?

The ARPA may swap targets when automatically tracking if two targets _____________

You are using a radar in which your ownship is shown at the center, and the heading flash always points at zero. If bearings are measured in relation to the flash, what type of bearings are produced?

A radar contact will remain stationary on a relative motion radar display only when it is _________________

These are methods of Collision Avoidance, except ____________________

Target aspects are measured from _______________

A radar range to a small, charted object such as light will provide a line of position in which form?

The most accurate position by radar fix is _________________

What is the process of observing the sequential changes in the position of a target, to establish its motion?

Does the COLREGS give any preference to ships equipped with ARPA?

Using the control STC on RADAR, at what distance does sea return disappear?

The sensitivity of the ARPA tracking system is increased when operating in automatic acquisition mode.

The echoes are remained between guard rings when the search area philosophy is used by the ARPA tracking system.

The processing time depends on the antenna rotation time.

The information on the ARPA is always on delayed time in relation to “real life” and this fact must be taken into account at all times.

One of the reason for loosing targets in the ARPA system is when the target entering the abeam sector.

As range increase the accuracy of bearing and range information and tracking accuracy increases.

Accuracy of the vector will only be within acceptable limits after five minutes of steady tracking.

The target causing the warning shall be clearly indicated on the display.

Only a flashing warning is activated whenever the system no longer track a target.

Own ships position input must be kept. Correct on the ARPA at all times.

ARPA can acquires 10 targets automatically.

Rain clutter suppresses over the whole screen and can also suppress small targets which is a danger.

The antenna rotates in Stand by status.

The best tuning point condition is where the tuning indicator lights to about 80% of its total length.

In True motion mode, Own ship and other moving objects move in accordance with their relative courses and speeds.

In North Up mode, the heading marker changes its direction according to the ship’s heading.

For stable reception of certain types of radar beacons (racons) or SART (Search and Rescue Radar Transponder) as required by SOLAS 1974 as amended 1988 (GMDSS), it is recommended to turn the interference rejector on

A target entering the guard zone produces both visual (flashing) and audible (beeping) alarms.

The anchor watch feature helps you monitor whether other ship is dragged by wind and/or tide while at anchor.

True vectors can be displayed relative to own ship’s heading (Relative) or with reference to the north (True).

_________ controls the overall amplification of all returned echoes.

The _____________ reduces mutual radar interference.

This ____________ shows trails of target echoes in the form of simulated afterglow.

The HM is used to temporarily ________ the heading marker.

This ___________ provides an accurate measurement of range to targets.

_____________ adjusts the brightness of range rings

Selecting a short pulse length will ___________ range discrimination, making it possible to distinguish between a tug and its tow for instance.

The FTC will _______ the interference on the screen due to the rain and increase the chance of seeing targets within rain showers.

The STC is a form of swept gain control which turns _____ the gain in the area of the screen where sea clutter echoes are found.

The ___________ converts the transmitted/ received frequency of the radio wave back to a lower immediate frequency to allow proper amplifications of the returned echoes.

Wavelength indicates the number of crests, which pass a fixed point per unit time.

X-band radar has a wavelength of 10 cm.

Magnetron converts the input into high frequency oscillation.

The receiver amplify the incoming echoes.

A radar sweep is one complete 360 degree rotation of the antenna.

A long pulse means better resolution in range.

A short pulse means less resolution in range.

The bearing accuracy is generally better than the range accuracy of a radar.

The duplexer ensure that all circuits connected to the radar system operate in a definite time relationship with each other.

The antenna transfers the transmitter energy to signals in space with the required distribution and efficiency.

is a radar's capacity to distinguish between close-proximity targets on the same bearing.

is a radar's capacity to distinguish between close-proximity targets at the same distance.

The lower portion of the target won't be visible if the radar horizon is between the transmitting vessel and the target.

also known as rain control for anti-clutter.

occurs when a ship and a relatively close target, such as another ship, engage in radar beam bouncing.

occurs when a huge radar target hides a smaller target behind it or when the curvature of the Earth hides a target.

Antenna not placed at the ships highest point. Structures above antenna will create blind sector in radar screen. Objects within this sector will normally be invisible in the screen.

If the target does not rise above the radar horizon, the radar beam cannot be reflected from the target.

Targets having larger reflecting areas return stronger echoes than targets having smaller reflecting areas.

The orientation to the axis of the radar beam. The nearer the angle between the reflecting and the beam axis is 90 deg., the greater is the strength of the echo returned to the antenna.

Targets of identical shape may give echoes of varying strength, depending on aspect.

A smooth surface will give poor radar echo because most of the energy is reflected in another direction.