Basic Navigation Flashcards
Statute mile (SM) in feet
5280’
5280’
Statute mile (SM)
1 SM = __ NM
.87 NM
2 types of navigational reference lines?
Parallels
Meridians
Which direction do parallels run?
East/west (latitude)
What reference lines run east/west?
Parallels
Where is the only great circle Parallel?
Equator: 0 degrees latitude
What is the range of Parallels in degrees?
90 degrees north to 90 degrees south
Which direction do Meridians run?
North/south (longitude)
What reference lines run North/south?
Meridians
What meridian is at 0 degrees longitude?
Prime meridian
Where is the Prime meridian?
0 degrees longitude
Which (latitude or longitude) lines make up 1/2 of a great circle?
All longitude lines make up 1/2 of a great circle
Are all longitude lines 1/2 of a great circle?
yes
What is the range of meridians in degrees?
0° to 180° East/West
How are parallels/meridians measured?
Degrees
Minutes
Seconds
EX: (35°20’15”)
Where does the compass direction go in the parallel/meridian measurement?
The end
EX (35°20’15” N)
What fraction are minutes and seconds to their parent unit (degrees are the parent unit of minutes)?
1/60th
I.E., 60 minutes make one degrees and 60 seconds make a minute.
At the equator, how many NMs does 1’ of longitude equal?
1 NM
Are SMs used for visibility?
Yes
What measurement of distance is used to measure visibility?
SM
What measurement of distance is used for everything except visibility?
NM
What is UTC?
Coordinated Universal Time
Coordinated Universal Time (UTC)?
Greenwich Mean Time (GMT), Zulu (Z)
24-hour clock
How many degrees longitude are time zones?
15 degrees
What does a “knot” measure?
Speed
How many NMs per hour is 1 KT?
1 NM per hour
What are the 4 types of airspeed?
Indicated (IAS)
True (TAS)
Ground (GS)
Mach
What is Indicated (IAS) used for?
ATC communications
What type airspeed is used for ATC communications?
Indicated (IAS)
What airspeed is shown on the aircraft’s airspeed indicator?
Indicated (IAS)
Where is Indicated (IAS) shown?
the aircraft’s airspeed indicator
What does True airspeed not take into account?
The wind
What is true airspeed used for?
Flight planning
En route
What is ground speed (GS)?
Speed of the aircraft over the ground.
How is ground speed calculated?
True speed +/- wind effects.
What type speed is calculated with True speed +/- wind effects?
ground speed (GS)
What ratio is mach?
True airspeed : speed of sound
How is mach expressed?
In decimals
EX mach 0.9
What are the 3 main environmental effects?
Altitude
Temperature
Wind
How does altitude affect speed measurements?
Air density affects aircraft speed.
Higher altitude will show IAS lower than actual GS
How does temperature affect speed measurements?
Higher air temperature lowers air density
Same effects as altitude, but less pronounced
How does wind affect speed measurements?
Head/Tail winds add or reduce an aircraft’s ground speed
Crosswinds affect speed and course
How do Head/Tail winds affect speed measurements?
True airspeed +/- wind speed = GS
Add tailwind
Subtract headwind
How do Crosswinds affect speed measurements?
Cause aircraft to drift.
EX: 10KT wind over one hour will blow the aircraft 10NM off course
What are the 5 types of navigation?
Waypoints charted by Lat/Long or bearing/distance from a NAVAID Radio Navigation Dead reckoning RNAV GPS
How does Dead Reckoning work?
predetermined course
Corrects speed and headings
Accounts for wind
Can include ground references in VMC
How does Radio Navigation work?
Ground based radios transmit nav aids to aircraft
How does RNAV work?
Computed waypoints
Where are Waypoints charted by Lat/Long or bearing/distance from a NAVAID approved?
Only where there’s ATC radar monitoring
Is GPS affected by weather?
No
What is magnetic variance?
The difference between true and magnetic north
What is true north?
the geographic north pole
Does magnetic north move?
Yes
Does ATC use magnetic headings?
yes
