Chapter 1: Introduction to Navigation

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Chapter 1 Introduction to Navigation

• Instructor Walter Spall

Selected Questions Study these for exam
PowerPoint Presentation by Forrest Meiere
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S1-6. The process of predicting the future
position from knowledge of its present position,
course steered and speed is termed
___________________.
dead reckoning (DR)
S1-7. The earth revolves about an axis passing
through the earths center and intersects the
surface at two points, termed ___________________
___________.
north and south geographic poles
S1-8. A plane passing through the earths center
intersects the surface to produce a ____________.
great circle
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S1-9. On the surface of a sphere, the shortest
distance between any two points lies on a
____________ connecting them.
great circle
S1-10. If a plane passing through the earths
center is perpendicular to the axis of rotation,
it forms a great circle termed the _________.
equator
S1-11. The upper branch of the great circle
passing through the poles and Greenwich, England
is called the ____________________________________
.
prime meridian or Greenwich meridian
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S1-12. A circle contains ____ degrees. Degrees
are subdivided into ________ and
___________________________.
360
minutes seconds or tenths of
minutes
Longitude
S1-13. __________ (Lo) is the angle between a
position on earth and the prime meridian measured
east or west.
S1-14. A plane passed through the earth that does
not touch the earths center forms a ___________
on the surface.
small circle
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S1-15. The angle between a position on earth and
the equator measured north or south is
_______________________.
Latitude or Lat or L
S1-16. Any position on the earths surface can be
defined by specifying its ________ and
__________.
latitude longitude
latitude longitude
S1-17. One degree of _________ equals 60 nautical
miles. Not so for _________ except at the
equator.
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S1-18. Three common ways to specify direction are
___________________________.
true, magnetic, compass
S1-19. When a course crosses each meridian at the
same angle the resultant line is called a
____________ or ____________.

rhumb line loxodrome
weak magnetic field
S1-20. The earth has a __________________,
thought to be generated by the flow of the liquid
iron alloy core of the planet. (a little more
complicated than this FM)
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S1-21. At the surface of the earth, lines of
magnetic field are termed, __________________
analogous to __________ meridians.
(magnetic field, not force)
magnetic
meridians geographic
S1-22. The angle between geographic and magnetic
meridians is called _________________ or
_________.
magnetic variation variation
S1-23. Variation is said to be _____ if the
magnetic meridian points east of geographic north.
east
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S1-26. To convert from relative bearing to true
or magnetic use the equation
_____________ ______________
_______________. If this exceeds
_____, subtract ______.
ships heading relative bearing
objects bearing 360
360
S1-27. An object off the stern has a relative
bearing of ____ while one directly off port has a
relative bearing of _____.
180 270
outer circle true
inner circle magnetic north
S1-28. Normally, the ___________ of the compass
rose references _____ north while the
____________ references ______________.