Navigation 3 01 Foundations of Navigation References FTGU

Navigation 3. 01 Foundations of Navigation References: FTGU pages 177 -178, 184 -190 Transport Canada Study and Reference Guide Glider Pilot Canada Flight Training Manual – Pilot Navigation http: //en. wikipedia. org/wiki/Transverse_Mercator_projection#Spherical_transverse_Mercator

3. 01 Foundations of Navigation • MTPs: – Longitude and Latitude – Time and Longitude – Charts – Lambert Conformal Conic Projection – Transverse Mercator Projection – Great Circles and Rhumb Lines – Magnetic Navigation – Units of Distance and Speed

Longitude and Latitude • Imaginary lines make up a grid on the surface of the earth. • Parallels of Latitude run east to west (like the equator), and are numbered 0 to 90 degrees North and South from the equator. • Meridians of Longitude run north to south and are numbered 0 -180 degrees East and West from the Prime Meridian.

Longitude and Latitude • Latitude is measured in degrees, minutes and seconds and includes “north” or “south”. • The equator is at 0 degrees latitude. • Point A is at 15 degrees north.

Longitude and Latitude • Longitude is measured in degrees, minutes and seconds and includes “east” or “west”. • The Prime Meridian is at 0 degrees longitude. • Point A is at about 22 degrees west.

Longitude and Latitude • • • Coordinates are given by grouping the latitude and longitude of a point together in that order Each degree is broken into 60’ (minutes) and each minute is broken into 60” (seconds) The coordinates for Moose Jaw, Saskatchewan are: 50° 23′ 36″N 105° 33′ 07″W

Confirmation C B D A • What is the approximate latitude and longitude of each letter? A. ___________ B. ____________ C. ___________ D. ____________

Confirmation See if you can find the latitude and longitude for your home town. Google it and report it in the chat box!

Time and Longitude • Because the earth rotates, the sun appears to pass over a fixed point on the earth at a rate that varies throughout the year – If we take an average throughout the year, we can calculate the mean solar day • The mean solar day is divided into 24 equal hours – Each hour, the earth will rotate approximately 15 degrees – It will take the earth 4 minutes to rotate approximately 1 degree • This rate actually appears to vary, so we use a common reference – UTC (coordinated universal time) or Z (“Zulu” time) • Time at the prime meridian – Time zones are expressed in hours behind or ahead of UTC or Z • E. g. PST is UTC -8 and PDT is UTC -7

Charts • What is a chart? • Basic Elements of Map Construction: – Area – Shape – Bearing – Distance • Normally one of the elements is closely preserved, the others become distorted.

Charts • Projections are the mathematical basis upon which maps are constructed • Types of projections: Cylindrical Conic Azimuthal

Lambert Conformal Conic Projection • Parallels of Latitude are curved, and • Meridians of Longitude converge at the pole.

Lambert Conformal Conic Projection

Transverse Mercator Projection

Mercator Projection Parallels of Latitude and Meridians of Longitude are straight lines that form a grid.

Great Circles and Rhumb Lines • A great circle is a line that cuts the earth perfectly in half, and represents the shortest distance between two points – An example of a great circle is the equator • A rhumb line is a line which cuts each meridian it crosses at the same angle – A line which could be made by flying the same heading

Great Circles and Rhumb Lines } Drawing a straight line on different projections will yield different results } Lambert Conformal Conic Projection } Great Circle } Mercator (not Transverse Mercator) } Rhumb Line

Magnetic Navigation } The earth generates a magnetic field which is useful for navigation using a compass } This magnetic field is not perfectly aligned with the axis of rotation } This creates a magnetic north which is in a different geographic location from true north } The angular difference between true north and magnetic north is known as variation } This is expressed in degrees east or west of true north

Magnetic Navigation • Isogonic lines connect areas of equal variation • Agonic lines connect areas of 0 variation

Magnetic Navigation • It is possible to convert a true heading to a magnetic heading or a compass heading using the TVMDC method • More on doing this, and on using a compass, in 3. 03

Units of Distance and Speed • 1 Statute Mile (SM) is 5 280 feet • 1 Nautical Mile (NM) is 6 080 feet – 1 Knot is 1 Nautical Mile per Hour • The ratio of 1 NM to 1 SM is 1. 15

Confirmation Identify the type of projection. What are its characteristics?

Confirmation Identify the type of projection. What are its characteristics?

1650 Map of the Ancient World