Navigation Flashcards
What are the 5 Methods of Navigation?
Pilotage - Using reference to the surface
Dead Reckoning - “Point and Shoot” using the surface
Radio Navigation - Without reference to surface
Celestial Navigation - Using reference to stars
GPS Navigation - using the Global Positioning System to determine location
How many minutes in a degrees of lat/long and how many seconds in a minute?
60
Longitude lines are known as what? Latitude lines are known as what?
Meridians of Longitude
Parallels of Latitude
Describe Meridians of Longitude
Join the true poles of the Earth, run North to South, measure East and West of the Prime Meridian, distance between lines decreases as you get nearer to poles
Describe Parallels of Latitude
Run parallel to Equator, Measured North and South of the Equator, distance between lines is constant
How many degrees of Longitude are completed in one day? and how fast does the Earth spin in degrees of Longitude/hour
360 degrees of Longitude in a day. 15 degrees of Longitude an hour
Where is Standard Time located, and what is it known as?
Greenwich, England. Known as GMT, UTC, or Zulu
What Time system is used in all ATC or Meteorology services?
Zulu Time
How many time zones in Canada and name them
6 Time Zones
Pacific, Mountain, Central, Eastern, Atlantic, and Newfoundland
What is a Great Circle?
Line over the surface of the Earth that, if extended over the entire surface, it would cut it exactly in half
Is the Equator a Great Circle?
Yes
What does a Great Circle represent?
The shortest distance between two points on the Earth. However, aircraft must constantly adjust heading because it does not meet Meridians at same angle
What is Rhumb Line?
A curved line on Earth that meets each Meridian at the same angle
What are some Advantages and Disadvantages of Rhumb Lines?
Advantage: Allows pilots to fly a constant heading
Disadvantage: Unless track is on a Meridian, route is longer than Great Circle
What is the Difference between Heading and Bearing?
Heading is the direction the aircraft’s nose is pointed
Bearing is the direction of an object from an observer or our position relative to a point
Is the Earth a magnet?
Yes
What does a compass needle align itself with?
The North seeking end of the needle will always point towards magnetic North
What causes Magnetic Dip?
Earth’s magnetic lines are horizontal over the Equator, but vertical at the poles. In Northern Latitudes this causes the needle to point down
What is the Geographic Area where Magnetic Dip occurs called?
The Area of Compass Unreliability, or Northern Domestic Airspace
What allows us to make sure we are going in the right direction even though True North, and Magnetic North are in different places?
Magnetic Variation
What is an Isogonic Line, and what is an Agonic Line?
Isogonic Line is a line joining places of equal variation
Agonic line is a line joining places of zero variation
If magnetic pole lies west of true pole what must we do?
Add the variation on to True North
When is the Compass reliable?
During level constant airspeed flight, or constant rate climbs or descents
Does the Compass require any external power?
No
Explain the Construction of the Compass
2 North seeking magnets
Attached to float which has compass card attached to it
Mounted on a pivot
Filled with kerosene to dampen oscillations
Container has expansion chamber for temperature changes
Housing made of brass (non-magnetic)
What is the line on the compass that shows the direction you are going called?
The Lubber Line
Name and Describe 4 Compass Errors
Deviation - Needle can be deflected due to magnetic interference, must be corrected by knowing deviation and adding or subtracting depending on direction (Compass Card prepared by Compass Swinging)
Magnetic Dip - Already touched on, vertical magnetic lines at poles causes North to point down, compensated by balancing magnet on pivot point, centre of gravity below pivot point, and centre of buoyancy above centre of gravity
Northerly Turning Error - Turns to or from North lag or show turn in opposite direction, Turns to or from south lead. Max on headings of N or S, Min on headings of E or W
Acceleration and Deceleration Error - Acceleration causes compass to show turn to North, Deceleration causes turn to South, Max on E W headings, Min on N S headings
When can we reset the Heading Indicator?
Only when the compass is accurately and reliably showing information
When in GPS available for location services?
Available all over the world, in any weather condition
How many satellites make up the GPS system?
24 in 6 semi-synchronous orbits
How often does a Satellite complete an orbit?
Every 12 hours
How many Atomic Clocks does each Satellite contain?
4 (accurate to at least a billionth of a second)
Describe the 3 Segments of GPS
Space Segment - Satellites orbiting the Earth
Control Segment - Master Control Station (tracking, monitoring, and updating satellites) and Monitor Stations (checks altitude, position, speed, and health of satellites)
User Segment - GPS receiver and an antenna, must be on top of aircraft
How does GPS work what is the process of determining position?
Time required to reach receiver is translated into distance, the receiver will resolve signal arrival time, and corresponding satellite position to determine own position
How many Satellites are required for accurate position?
4
How many Feet in a Statute Mile? How many Feet (Minutes of Latitude) in a Nautical Mile? What is a Knot?
1 SM = 5280 ft
1 NM = 6078 ft (1 min of Latitude)
1 Kt = 1 NM/hr
Out of the 4 elements of maps (Area, Shape, Bearing, Distance), how many can be preserved in one map?
A max of 3 of the 4 elements can be preserved, at least one must be distorted
What are the 2 Map Projections that are used in Aviation charts/maps?
Lambert Conformal Conic
Transverse Mercator
What are some Properties of the Lambert Conformal Conic Projection?
Meridians are straight lines converging toward pole
Parallels curved away from near pole
Scale is accurate over map
Straight line between 2 points represents a Great Circle
What Aeronautical Charts use the Lambert Conformal Conic Projection?
VFR Navigation Charts (VNC) and IFR Enroute Charts (LO or HI)