Nav 02

Question 1

What is Air nav?

Answer 1

Finding out where you are, where you should be, and how to match the two

Question 2

What shape is the earth?

Answer 2

Oblate spheroid

Bulge in one axis compared to the other. Equator diameter is longer than the diameter from the poles

Question 3

Great Circle

Answer 3

Circle on the surface of the earth whose centre and radius are those of the sphere itself.

Divides a sphere into 2 equal hemisphere

Shortest distance between 2 points

When flying GC constant heading changes are required

Question 4

Equator

Answer 4

A great circle whose place is perpendicular to the earth’s axis of rotation

Question 5

Small Circle

Answer 5

A circle on the surface of the earth whose centre and radius are NOT those of the sphere itself

All circles on the surface of the earth that are not great circles are small circles

Question 6

Parallel (latitude)

Answer 6

A small circle on the surface of the earth whose plane is parallel to the equator

Angular distance from the equator measured along a meridian

Question 7

Meridian (longitude)

Answer 7

A semi- great circle joining the poles of the earth

All meridians converge at the poles

Angular distance from the prime meridian, measured along the shorter are of the equator

Question 8

Rhumb line

Answer 8

Regularly curved line cutting all meridians at the same angle

Allows a path of flight to be a straight line on some maps (Mercator projection)

When flying RL the heading remains constant

Question 9

Nautical mile (NM)

Answer 9

LENGTH OF AN ARC ON THE SURFACE OF THE EARTH SUBTENDING 1’ AT THE CENTRE OF THE CURVATURE OF THE PLACE

Varies a little

1 NM = 6080 ft = 1’ of latitude

Question 10

Statute mile (SM)

Answer 10

Arbitrary unit of measurement

1 SM = 5280 ft

Used for met