WorksheetsNAV 1 REVIEW 2
Total questions: 20
Worksheet time: 10mins
How should a mariner adjust the echo-sounder to avoid shallow water clutter?
Increase the stylus speed setting
Adjust the gain and pulse length
Change the transducer location
Disable the depth recorder unit
What action ensures depth is measured from the keel, not the transducer?
Set the correct draft offset
Increase the stylus voltage
Adjust the zero line setting
Reposition the display unit
How can a mariner correct for cross noise on the echo-sounder display?
Increase the chart scale setting
Adjust the swept gain control
Disable the stylus motor unit
Recalibrate the transducer angle
What should be done when multiple echoes appear on the depth trace?
Reduce the stylus speed setting
Adjust the gain and pulse length
Reposition the transducer mount
Increase the chart paper feed
How is UKC determined using echo-sounder data?
Subtract draft from measured depth
Add draft to measured depth value
Multiply depth by ship’s beam size
Divide depth by ship’s length overall
What step helps correct stylus speed error during operation?
Stabilize voltage to stylus motor
Increase gain to reduce clutter
Adjust zero line to match depth
Reposition transducer near keel
How should a mariner respond to false echoes from thermal layers?
Increase stylus speed for clarity
Adjust gain and verify seabed trace
Disable transducer and restart unit
Recalibrate the depth scale setting
What is the correct way to operate the echo-sounder for UKC?
Disable alarms and increase gain
Adjust stylus speed and chart scale
Use prescribed settings and manual
Reposition transducer and receiver
How can aeration be identified on the echo-sounder display?
Dots and irregular marks appear
Depth trace becomes a straight line
Stylus burns through chart paper
Gain control resets automatically
What should be done when trim and heel affect depth readings?
Adjust draft offset and scale
Disable transducer and restart chart
Increase stylus speed and gain
Level the ship and recalibrate unit
A chart indicates 50 meters but the sounder reads 47 meters. Apply the best adjustment for accuracy.
Check sound velocity input
Change paper recording speed
Shift transducer forward
Increase pulse repetition rate
A ship uses bathymetric navigation. Apply knowledge to identify which feature must be compared with charts.
Magnetic compass bearings
Atmospheric pressure values
Ocean surface wave heights
Geological seabed profile
A return echo is too weak over soft mud seabeds. Apply the adjustment needed on the equipment.
Increase gain sensitivity
Lower transmitted frequency
Shorten transmitted pulses
Decrease chart paper speed
A survey requires depth in fathoms. The sounder shows 36 meters. Apply the conversion to fathoms.
18 fathoms
20 fathoms
24 fathoms
12 fathoms
How should a mariner respond when the echo sounder shows multiple echoes stacked below the seabed line?
Calibration adjustment line
Actual seabed position
Double reflection error
Incorrect frequency setting
A vessel in deep water has long pulse intervals. Apply the best operator action.
Use deeper range scale
Reduce chart paper speed
Increase gain sensitivity
Lower transmitted frequency
A ship displays readings in meters but the navigator needs fathoms. Apply the correct setting.
Increase pulse repetition rate
Change display unit scale
Relocate transducer position
Shorten transmitted pulses
Alexander Behm’s invention was applied after 1912. Apply its use to marine navigation today.
Detecting icebergs ahead a
Determining wind strength
Identifying vessel traffic
Measuring depth of sea
How should a mariner identify the true seabed echo when a vessel encounters false echoes?
Select the strongest echo
Increase recording speed
Adjust to a deeper scale
Lower transmitted power
A vessel operates echo sounder in shallow water. Apply the setting to avoid overlapping echoes.
Increase chart paper speed
Lower sound velocity input
Use shorter pulse length
Relocate transducer forward
