Grivation, Highest lat of G.C track, G.C vertices (05-06-18)

Question 1

What is grivation?

Answer 1

The angle between magnetic north and grid north

Question 2

What are chart lines that join points of equal grivation called?

Answer 2

Isogrivs

Question 3

What is the equation for calculating the highest latitude reached by a G.C?

Answer 3

Original lat + x

x = (CA + total R.L distance)/230

(in nm)

Question 4

What are G.C vertices?

Answer 4

The points of a G.C that reach the highest latitudes and are antipodal.

Question 5

How do the longitude and latitude of each G.C vertex compare to each other?

Answer 5

N/S lat are the same value just in opposite hemispheres

E/W longitude values sum to 180deg

Question 6

When considering G.C vertices, when is the equator crossed?

Answer 6

At the mid point (90deg) between the vertices.

Question 7

What can be said about the track at the equator when a G.C crosses it and the vertices are known?

Answer 7

The track, from south to north, is equal to the latitude of the vertices.