Flight Navigation General Flashcards
What is an isogonal?
A line joining points of equal magnetic variation.
When flying from Auckland to Perth on a great circle, will the track be a curve or straight line if you were using a Lamberts chart?
Great circles are straight lines on Lamberts charts.
Explain a mercator projection
- Turns a sphere into a cylinder
- All meridians are straight lines with parallel spacing
- Rhumb line will appear straight
- Great circle appears curved.
Explain a Small Circle
Any circle drawn on the earth whose radius is not the earth.
How do you calculate TAS given IAS?
TAS = IAS + (miles a minute x alt in thousands )
How do you calculate bank angle for a rate 1 turn given airspeed?
Bank angle = (TAS/10) x 1.5 or + 7.
Formula for turn radius / arc turn on?
Turn radius = 1% of TAS / 2.
What is earth convergency?
The angle of inclination between two meridians at a given latitude.
What is the speed of rotation of the Earth?
900kts at the equator
Speed = 900 x cos(latitude)
How do you calculate a reciprocal heading
Initial heading ± 200 ±20.
What is a Great Circle
A circle drawn on the surface of the earth whose radius is the earth. The shortest distance between two places.
When flying from Auckland to Perth on a great circle track, what happens to heading?
It slowly increases as great circles are concave to the equator on Mercator charts.
Explain lambert projection
- turns a sphere into a cone
- meridians are straight lines
- lats and longs intersect at right angles
- rhumb lines are curved concave to poles
- great circles are straight.
Explain a Rhumb Line
A line drawn on the earth’s surface which cuts each meridian at the same angle.
What is the conversion angle?
Angular difference between the great circle track and rhumb line track between two points.