Navigation Flashcards
Air Navigation definition
determine geographic position and maintain desired direction of an aircraft relative to the surface of the earth
position
geographic point defined by coordinates
latitude
angular distance north or south of the equator 0= equator 0-90 degrees curved on Lambert conformal chart. latitude is measured along meridian
longitude
angular distance east or west of prime meridian
0 = meridian, 180 = international date line.
straight lines on Lambert conformal chart
longitude is measured along parallel lines
how many minutes in a degree
60 minutes in a degree
dead reckoning
directing an aircraft and determining its position by the application of direction and speed data from a previous position
dead reckoning components
PTSD
position, time, speed, direction
direction
angular distance from a reference. measured 001-360 degrees
primary instrument for determining direction
BDHI - bearing distance heading indicator (remote gyro vertical compass)
ring laser gyro highly accurate without lag
secondary or backup direction measurment instrument
stand by compass
wet compass, reliable (does not require eletricity) but is unstable during maneuvers
Time
00+00
00+00+00
00: 00
00: 00:00
ETE estimated time en route
expressed in hours : minutes
or hr + min
speed
distance / time
three primary instruments for dead reckoning
BDHI (direction and position)
clock (time)
airspeed indicator (IAS)
two secondary instruments
altimeter
outside air temp - OAT
what variables are used to convert IAS into TAS
altimeter and outside air temp
visual navigation
navigation by ground references (bld, river)
electronic navigation - and its 3 categories
use of electronic devices to determine position
1) receive signals from EXTERNAL SOURCES
GROUND STATIONS - VOR, TACAN
SPACE - GPS
2) IN BOARD signals - RADAR, DOPPLER
3) self contained - INERTIAL NAVIGATION SYSTEM (INS)
- requires pilot input of starting location
Type of electronic navigation which recieves input from space
GPS
Great Circle
circle formed by continuing arc inscribed by connecting the shortest distance between two points on a sphere.
circle which plane passes through the center of the earth
EX: every longitude, and the equator
Lambart conformal projections
conic projections
parallels - equally spaced concentric circles
meridians - straight lines converging at poles
great circle - plot as straight line
scale is constant
Operational Navigation Chart (ONC) - scale and properties
1:1,000,000
less detail, larger area
world wide coverage
Tactical Pilotage Chart (TPC) - scale and properties
1:500,000
more detail, smaller area
world wide coverage
Course
aircrafts INTENDED flight path
Heading
angular distance of the aircraft’s longitudinal axis from reference (TN or MN).
where HEAD of aircraft is pointing
Track
aircrafts actual flight path over the ground
variation
angular difference between true north and magnetic north
isogonic line
connects points of equal variation
East is Least, Best is West
MC = TC - East variation MC = TC + West variation
degrees in 1 hr (time zone)
15 degrees / hr
1 hr = 15 degrees
(360 degrees / 24hr)
Divider
measuring distance on a chart
plotter
combination protractor and straightedge. used ot aid in drawing course lines and measuring direction
when measuring distance, how long is 1 minute latitude?
1 NM = 1 min lat
LA GS
when solving for pressure altitude, if measured pressure is less than standard (29.92) then add. if greater than standard subtract.
nautical mile
one minute of arc measured along any great circle
vector
possesses both direction and magnitude
air vector
the aircraft’s direction and speed represented by True Heading (TH) and True Airspeed (TAS)
ground vector
the aircraft’s intended or actual flight path (True Course or Track) and Ground Speed (GS)
wind vector
winds direction TRUE (DIR) and Velocity (VEL)
Drift angle
the difference between true heading and track
crab angle
the amount of correction an aircraft must be turned into the wind in order to maintain the desired course.
absolute altitude
actual height of aircraft above the surface of the earth (AKA AGL)
Pressure altitude
CALIBRATED altitude corrected for difference between local atm P and standard 29.92
(LA GS)
indicated altitude
reading on the aircraft altimeter when set to the local area barometric
calibrated altitude
altitude corrected for instrument and installation error
True altitude
actual height of the aircraft above MSL. Found by correcting calibrated altitude (CA) for density.
temperature variation causes how much altimeter error?
11 C temperature change from standard causes 4% altimeter error
Indicated airspeed
IAS - airspeed read directly from the aircraft airspeed indicator
calibrated airspeed
Indicated airspeed corrected for instrument installation error.
True airspeed
TAS is calibrated airpseed corrected for air denisty. Speed of aircraft through the air mass
ground speed
actual speed of the aircraft relative to the ground. TAS corrected for head wind/tail wind.
Gyro vertical compass card aka BDHI
-what is the point of the second needle represent?
MAGNETIC bearing to the TACAN in radials
Gyro vertical compass card aka BDHI
-what is the tail of the second needle represent?
Current radial (i.e. radial from the station to aircraft)
Gyro vertical compass card aka BDHI
-what does the top of the dial on a BDHI represent?
heading (where the nose of the aircraft is pointed)
Gyro vertical compass card aka BDHI
-what is the DME?
technically the slant range, however we consider it the horizontal distance from the aircraft to the TACAN
Jet log primary purpose
Fuel management
course control vs turn point navigation
course control: adjust route to stay on track multiple times.
turn point: once off track, make single correction to return to a single point on track
