PHILIPPINE MERCHANT MARINE ACADEMY
DEPARTMENT OF MIDSHIPMEN AFFAIRS
PMMA COMPLEX SAN NARCISO ZAMBALES
FINAL EXAMINATION SCORE
1ST / 2ND SEMESTER SCHOOL YEAR 2020-2021
Final Exam Navigation 3
SUBJECT
NAME _____________________________ DATE _____________________
CLASS / SECTION ____________________ INSTRUCTOR: ______________________
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I. Fill in the blanks (2pts each)
1. Nautical Mile - Is the unit of distance used by navigators at sea and in the air. For most
practical purposes it is considered to be a length of 6,080 feet or 1,852 meters. For most
navigational purposes the nautical mile considered a length of one minute of latitude.
2. Knot - is a navigational unit of speed. One knot means “a speed of one nautical mile per
hour”. It may also state that speed is rate of motion, or distance per unit of time. Speed
(S) is the rate of motion, the distance traveled in units of time (T), then D = S X T
3. Nautical chart - is a graphic representation of a maritime area and
adjacent coastal regions
4. Map - is defined as a representation, usually on a flat surface, of a whole or part of an
area. Maps can display political boundaries, population, physical features, natural
resources, roads, climates, elevation (topography), and economic activities.
5. Sailing charts - are the smallest scale charts used for planning, fixing position at sea, and
for plotting the dead reckoning while proceeding on a long voyage. The scale is generally
smaller than 1:600,000. The shoreline and topography are generalized and only offshore
soundings, the principal navigational lights, outer buoys, and landmarks visible at
considerable distances are shown.
6. Range - Two or more objects in line. Such objects are said to be in range. An observer
having them in range is said to be on the range. Two beacons are frequently located for
the specific purpose of forming a range to indicate a safe route or the centerline of a
channel.
7. Leading line - On a nautical chart, a straight line, drawn through leading marks. A ship
moving along such line will clear certain dangers or remain in the best channel.
8. Range lights, leading lights - Two or more lights at different elevations so situated to
form a range (leading line) when brought into transit. The one nearest to the observer is
the from light and the one farthest from the observer is the rear light. The front light is at
a lower elevation than the rear light.
9. Visual range - The extreme distance at which an object of light can be seen.
10. Geographic range - The extreme distance limited by the curvature of the earth and both
the heights of the object and the observer.
II. Choose the correct answer, draw a line from Colum A to B (2 pts each)
A B
1. MHWS Mean Low Water Spring
2. HW Mean Level
3. MHWN Low Astronomical Tide
4. ML High Water
5. MLWN Mean High Water Spring
6. MLWS Mean High Water Neap
7. LAT Mean Low Water Neap
8. ECDIS International Maritime Organization
9. ECS Electronic Chart Display and Information System
10. IMO Electronic Chart System
III. On your own word explain the fallowing (5pts each)
1. Explain the principle of a Magnetic Compass
2. The magnetic compass is the most familiar compass type. It functions
as a pointer to "magnetic north", the local magnetic meridian, because
the magnetized needle at its heart aligns itself with the horizontal
component of the Earth's magnetic field
2. How do a Gyro Compass Works
Gyrocompass, navigational instrument which makes use of a
continuously driven gyroscope to accurately seek the direction of true
(geographic) north. ... It operates by seeking an equilibrium direction
under the combined effects of the force of gravity and the daily rotation
of Earth.
IV. Problem Solving (10 Pts)
1. A vessel on a course of 055° by gyro and 041° by magnetic compass. The gyro error is 1
°W. The variation is 15 ° E. What is the Deviation on this Heading?
Given: Gyro Co - 055 ° True Co - Magnetic Err -
Gyro Err - 1°w Magnetic Co - 041 ° Variation - 15 ° W
True Co - Magnetic Err - Deviation
A B C
D E
Choose Which Letter Correspond Each Buoy from Above ( 2 pt each )
1. Special Bouy and Mark - ____D______
2. Cardinal Bouys - ____A______
3. Safe Water Marks - ____E______
4. New Wrecks Mark - ____C______
5. Isolated Danger Mark - ____B______
