Nav 03

Question 1

Direction

Answer 1

Position of one point in space relative to another, without reference to the distance between them

Angle that a live makes w/ some reference datum line passing through the point

Always measured clockwise from the datum

Always expressed in a three figure group

Question 2

Quadrant points

Answer 2

NE, NW, SE, SW

Question 3

Sexagesimal

Answer 3

Base of 60, used for time and direction

Question 4

East

Answer 4

Direction in which the earth is spinning

Question 5

West

Answer 5

Direction opposite to East

Question 6

North

Answer 6

Direction of the North Pole

Question 7

South

Answer 7

Direction opposite to North

Question 8

True direction

Answer 8

Direction measured w/ reference to the direction of the geographic North Pole

Question 9

Magnetic direction

Answer 9

Direction measured w/ reference to the direction of mag North at the place

Question 10

Magnetic force

Answer 10

2 regions on the surface of a magnet where its attractive force is the greatest

Attractive force is treated as if it emanates from 2 internal points called poles

Poles are the position of the greatest field intensity

Question 11

Magnetic Meridian

Answer 11

Direction of the horizontal component of the earth’s magnetic field at a point

Question 12

Secular change

Answer 12

Average value changes in the earth’s magnetic field over time, reflecting changes in the earth’s core = unpredictable

Question 13

Local anomaly

Answer 13

Anomaly caused by metal on earth or man made materials

Question 14

Annual variation

Answer 14

Average monthly values of the magnetic elements are corrected for secular change

Question 15

Magnetic storms

Answer 15

Solar flares cause irregularities in the earth’s magnetic field

Question 16

Soft iron magnetism

Answer 16

Caused by the magnetism induced into soft material. Consists of magnetic fields induced solely by the earth’s magnetic field

Varies w/ changes in heading and magnetic latitude

Question 17

Isogonal

Answer 17

Line on a map joining points of equal variation

Not coincident w/ the magnetic meridian and therefore does not indicate the direction of the earth’s field at a point

Question 18

Agonic line

Answer 18

Line on a map joining points of zero variation

Question 19

Variation

Answer 19

Horizontal angle between true north and magnetic north

West is best, East is least

Question 20

Hard iron magnetism

Answer 20

Caused by the permanent magnetism (metal structures) and DC circuits of the a/c

Remains constant w/ changes to heading and magnetic latitude

Question 21

Deviation

Answer 21

Angular difference between compass north and magnetic worth

West is best, East is least