23 Grid Navigation Flashcards
1
Q
Describe a Standard Grided Chart
A
- A Polar Stereographic chart with the grid aligned with the Prime Meridian
2
Q
What is Grid Convergence?
A
- Grid Convergence is the difference between True North and Grid North
- Grid Convergence is zero at the reference meridian
3
Q
How can you calculate Grid Convergence?
A
- Grid convergence value is equal to the change in longitude (degrees) between the datum meridian and the point
- Since Constant of the Cone = 1
- Direction: if true north is east of grid north than GC is east and vis-versa for west
4
Q
What is the phrase regarding Grid Convergence and East and West?
A
- Grid Convergence East, True Least
- Grid Convergence West, True Best
5
Q
What is the formula for Grivation?
A
Grivation = Grid Convergence + Variation
- East is +
- West is -
6
Q
What is a line of constant Grivation called?
A
Isogriv