NN310 ACTUAL EXAM QUESTIONS WITH ANSWERS 2025/2026
GRADED A+
DNC (Digital Nautical Chart) - Are broken into general,Harbor, Coastal and approach
Civilian Applications for GPS - Search and Rescue
Maritime Navigation
Land Navigation
Air Navigation
Military use of GPS - Search and rescue
Missile Guidance system
Navigation
Data Collection
Navy Use of GPS - -Search and rescue
Navigation
Amphibious Assault
Datum - Is a reference point for a coordinate system. A datum defines how the
coordinate grid is used.
STELLA - System to estimate Latitude and Longitude Astronomically
What is Celestial Navigation - Ancient Science of Navigation using stars and planets
What is EBL - Electronic Bearing Line-
-Can be used to determine the bearing /drift -
movement of a contact.
Assist Identify Landmarks
Marks Turns.
What Radar tool is used for Anchoring - Variable Range Marker
VRM - Variable Range Marker
-Marks Turns, Set ranges for contacting report, Set Ranges to Monitor Distance to land
or radar aid.
Maintain Position in Channel by monitoring cross check error.
Radar Function Rain - Returns from Atmospheric Conditions
Radar Function Sea - Sea Clutter
Radar Function Gain - Amplification Of sea Radar Return
Filters to remover Clutter - Rain and Sea
, Altitude - The Angular distance above the horizon that a celestial body is measured
Altitude Intercept Method - Using the difference between HC and HO to represent the
differences in circles in equal "altitudes between our assumed position and actual
observed position"
Assumed Position - DR position at time of observation, which be refined slightly for
convenience of sight reduction
Azimuth - True Bearing from the AP to the observed celestial body's geographical
position.
Celestial Horizon - A plane passing through the earth's center perpendicular to the
observers position
Celestial ( Astronomical Triangle ) - A triangle formed on the celestial sphere where its
vertices consisting of the celestial body, the elevated pole (either ps or pn ) and the
observers zenith
Celestial Sphere - A perfect sphere surrounding the earth with infinite radius.
Circle of Equal Altitude - a circle of points seeing a celestial body at the same altitude /
angle centered around the geographical position of the celestial body
Declination - The Measured Angle of a celestial body above or below the the
equinoctial. Similar to measuring latitude above or below the equator in terrestrial
coordinate system.
Equinotical - A theoretical extension of the earth's equator, forming the celestial equator
in the celestial sphere.
Geographic Position - The point on the earth directly below the celestial body.
Greenwich Hour Angle - The hour angle west of the greenwhich meridian o-359
Height Apparent - Measured Angle of Celestial Body over the horizon after sextant
corrections have been applied.
Height Computed/ Calculated - A calculated Angle of a celestial body over the horizon
based on the assumed position.
Height Observed - Measured Angle of a celestial body over the horizon after sextant
and all other corrections have been made.
Height Sextant - A measured angle of a celestial body over the horizon obtained by a
sextant reading.
GRADED A+
DNC (Digital Nautical Chart) - Are broken into general,Harbor, Coastal and approach
Civilian Applications for GPS - Search and Rescue
Maritime Navigation
Land Navigation
Air Navigation
Military use of GPS - Search and rescue
Missile Guidance system
Navigation
Data Collection
Navy Use of GPS - -Search and rescue
Navigation
Amphibious Assault
Datum - Is a reference point for a coordinate system. A datum defines how the
coordinate grid is used.
STELLA - System to estimate Latitude and Longitude Astronomically
What is Celestial Navigation - Ancient Science of Navigation using stars and planets
What is EBL - Electronic Bearing Line-
-Can be used to determine the bearing /drift -
movement of a contact.
Assist Identify Landmarks
Marks Turns.
What Radar tool is used for Anchoring - Variable Range Marker
VRM - Variable Range Marker
-Marks Turns, Set ranges for contacting report, Set Ranges to Monitor Distance to land
or radar aid.
Maintain Position in Channel by monitoring cross check error.
Radar Function Rain - Returns from Atmospheric Conditions
Radar Function Sea - Sea Clutter
Radar Function Gain - Amplification Of sea Radar Return
Filters to remover Clutter - Rain and Sea
, Altitude - The Angular distance above the horizon that a celestial body is measured
Altitude Intercept Method - Using the difference between HC and HO to represent the
differences in circles in equal "altitudes between our assumed position and actual
observed position"
Assumed Position - DR position at time of observation, which be refined slightly for
convenience of sight reduction
Azimuth - True Bearing from the AP to the observed celestial body's geographical
position.
Celestial Horizon - A plane passing through the earth's center perpendicular to the
observers position
Celestial ( Astronomical Triangle ) - A triangle formed on the celestial sphere where its
vertices consisting of the celestial body, the elevated pole (either ps or pn ) and the
observers zenith
Celestial Sphere - A perfect sphere surrounding the earth with infinite radius.
Circle of Equal Altitude - a circle of points seeing a celestial body at the same altitude /
angle centered around the geographical position of the celestial body
Declination - The Measured Angle of a celestial body above or below the the
equinoctial. Similar to measuring latitude above or below the equator in terrestrial
coordinate system.
Equinotical - A theoretical extension of the earth's equator, forming the celestial equator
in the celestial sphere.
Geographic Position - The point on the earth directly below the celestial body.
Greenwich Hour Angle - The hour angle west of the greenwhich meridian o-359
Height Apparent - Measured Angle of Celestial Body over the horizon after sextant
corrections have been applied.
Height Computed/ Calculated - A calculated Angle of a celestial body over the horizon
based on the assumed position.
Height Observed - Measured Angle of a celestial body over the horizon after sextant
and all other corrections have been made.
Height Sextant - A measured angle of a celestial body over the horizon obtained by a
sextant reading.
