1. CHARTS Graticule - grid over the globe made up of circles
Parallels of Latitude
Meridians of Longitude
Prime Meridian
International Date Line

2. Meridians of Longitude
Circles that pass directly through the North and South poles (true poles)
Meridians are measured 180 degrees east and west of the prime meridian
Prime meridian passes through Greenwich, England
International Date Line is
the meridian 180 degrees
opposite the prime meridian

3. Parallels of Latitude
Circles on the earth surface that lie parallel to the equator
The equator is the line of latitude that is equidistant between the poles.
Circles of latitude get smaller
and smaller towards the poles
Small
Circles
Equator = Great Circle

4. Both Longitude and Latitude are measured in degrees, minutes, seconds.
(60 minutes in a degree, 60 seconds in a minute)

5. Longitude 0o to 180o East and West from prime meridian
Degrees 0
Minutes ’
Seconds ”

6. Meldrum Bay is at
’ 35 ” lat
’ 10 ” long

7. 1 knot is slighter faster than 1 mph
One nautical mile is 6080 feet, a statute mile is 5280
A nautical mile is one minute of arc along a great circle
6080 feet to feet
70 to 60
1.15 to 1
1 knot is slighter faster than 1 mph
60 knots = about 70 mph

8. Questions What is located at N44˚27’30”W080˚09’30” ?
What is the distance from the Equator to the North Pole?
What is the distance between N42˚00’00” W081˚33’20” and N43˚50’00”W081˚33’20” ?
Collingwood Airport
Melbourne Airport
5400 NM
110 NM

9. MEAN TIME
Time between two transits of a meridian is apparent solar day – varies
Mean sun travels at assumed constant speed
Mean solar day same all year
360o passes in 24 hours so 24 hr = 360o
1 hr = 15o 1 min = 15’ 1 sec = 15”
Local mean time set to mid-meridian 15o

10. Great Circles
Great circles are lines drawn directly around the Earth that will cut it into two equal halves.
The cut would take
place directly through
the center of the Earth
Great circles are the
shortest distances between
two points on the Earth

11. Great Circle route

12. ADIS ABABA
LONDON
GREENLAND
VANCOUVER
CHARTS
Great circle or great circle route will be a circle that cuts through the center of the globe
Small circles – all parallels of latitude except the equator
All meridians are great circles

13. Rhumb Lines
A rhumb line crosses each meridian of longitude at the same angle.
Represents the path
of constant heading
between two points.
Not the shortest
distance.

14. How do we make a 2-dimensional map from a 3-dimensional Earth?

15. Waldseemuller’s Map of 1507

16. Mercator Projection Maintains constant distance between meridians.
This causes distortion
towards the poles.
Straight line on this
map is a rhumb line.

17. Transverse Mercator projection
Similar to mercator, except the mapping cylinder is rotated 90 degrees.
This allows the map-maker to center the projection on a meridian of longitude.
Good for small maps (VTAs) or for mapping a long narrow country like Chile
Map begins to
distort once you
move away from
the central meridian

18. Lambert Conformal Conic Projection
Map maker fits a cone over the Earth.
The points where the cone is touching the surface of the Earth are called the standard parallels.
Map is accurate at the
standard parallels but
distorts as you move away.
Used for medium scale
maps (majority of aviation
charts)

19. Lambert Conformal Conic Projection
Meridians of Longitude curve in towards the poles.
Straight lines represent great circles and therefore do not maintain constant headings (unless due north-south)

20. Great Circle/Rhumb Line on Mercator

21. Great Circle/Rhumb Line on Lambert Conformal Conic

22. VNC 5000

23. WAC Chart

24. VTA

25. Scale The scale used on a map depends on it’s use.
Large scale (WAC charts) displays a large area, but not a lot of detail
Small scale (VTA charts) displays a small area, and lots of detail
Medium scale (VNC charts) compromise between area and scale.

26. Scale
Ratio of chart length to the distance on the Earth it represents.
For example 1:500,000 means 1 inch on the map equals 500,000 inches on the ground.
*Remember* 1 minute latitude = 1 NM

27. Magnetic Variation
The magnetic north pole does not coincide with the true north pole.
Maps are aligned with true north, however our magnetic compass aligns with magnetic north
The difference between true north and magnetic north varies depending on your location and is called magnetic variation.

28. East Magnetic Variation
Subtract East Variation from true track to get magnetic track
Variation East – Magnetic Least

29. West Magnetic Variation
Add west variation to true track to get magnetic track
Variation West – Magnetic Best

30. Isogonal vs. Agonal
An isogonal line is a line joining points on the Earth with equal magnetic variation.
An agonal line is a line joining points on the Earth with zero magnetic variation

31. MAGNETIC DEVIATION Magnetic field from airframe, engine, electrical system. Compass card shows deviation & correction

32. MORE CHART STUFF CYR 511 all listed in CFS Military airfield
Parachute area
Abandoned airfield
Isogonic line
vs Agonic line

33. AGONIC LINE

36. CYKZ 1

37. CYKZ 2

38. CYKZ 3

40. OO 1

41. OO 2

42. PQ 1

43. PQ 2

44. QA 2

46. YZ TERMINAL