Navigation Flashcards
Air Navigation
The art and science of efficiently directing an aircraft from one place to another and determining the aircrafts position.
Essential problem of navigation
Where are we?
Where are we going?
How will we get there?
When will we get there?
Shape of the earth?
Oblate spheroid
Shape of the earth for Nav purposes
Perfect sphere
True Poles
Extremities of the diamater about which the earth rotates
Magnetic Poles
Extremeties of the diameter indicated by a north seeking compass
Great Circle
Line on the earths surface with the same radius and centre as the earth
Small Circle
Line on the earths surface with a radius and centre different to that of the earth
Equator
A great circle which is perpendicular to the axis of rotation and equidistant of both poles.
Meridians
Semi-great circles that join the poles
Parallels of Latitude
Small circles parallel to the equator
Rhumb lines
A regularly curved line that cuts all meridians at a constant angle
Problem of a flat map
Distortion
Properties of an ideal map
Conformality
Constant scale
Equal area
Great circles are straight lines
Rhumb lines are straight lines
Adjacent maps fit together
Geographic position easily fixed
Properties of conformality
Scale expanision/contraction is independant of azimuth/direction
Shape on chart conforms with area being portrayed
Meridians and parallels cut at right angles
Mercator Projection Properties
Great circle is curved convex to pole
Scale is constant only at the standard parallel
Bearings are correct
Rhumb lines are straight
Equator and meridians are only great circles with straight lines
