Aeronautical Charts and Units of Speed Flashcards
VNC
VFR Navigation Chart, scale is 1 to 500,000 (1inch to 8 miles) lambert
WAC
World Aeronautical Chart, scale of 1 to 1,000,000 (1inch to 16 miles) lambert
VTA
VFR Terminal Area Chart, scale of 1 to 250,000 (1inch to 4 miles)
Labert Conformal Conic Projections
- created by putting a cone of paper around the top of the earth
- meridians converge in the north
- VNC and WAC
- straight line on lamber conformal conic are great circles
- projection is better for longer distances
mercator projections
- created by a cylinder of paper around the earth
- meridians are parallel which is not true, creating distortion especially around the poles
- better for short distances
- straight line is a rhumb line
tranverse mercator projetions
rotates cylinder 90°so the point of tangency is on a line of longitude rather than latitude. makes for better accuracy, used for VTAs
enroute charts
provide info for radio nav over airways (do not show topical features)
LO - up to 18000ft
HI - 18000ft and up
CFS
Canadian Flight Supplement
revised every 56 days
info on canadian and north atlantic aerodromes
1NM = ?ft
6080ft
1SM = ?ft
5280ft
IAS
Indicated airspeed read off of ASI
CAS
Calibrated airspeed, IAS corrected for position and instrument error
TAS
CAS corrected for density and temperature. calculated with E6B or off ASI
ground speed
speed relative to the ground
heading vs track
heading is the direction the plane is facing whereas track is the direction its moving
drift
difference between heading and track
air position
position over earth in longitude and latitude
bearing
the angle from a given point
4 drift correction methods
1- visual
2- opening- closing angle method
3- double track
4- 1:60 rule
opening-closing angle method
correction= opening angle + closing angle
takes you to final destination
double track method
correction = opening angle x2 for the amount of time flown
puts you back on track
(cannot be used after halfway point)
1:60 rule
OA=(distance off course/distance flown) x 60
CA=(distance off course/distance remaining) x 60
OA+CA= correction
takes you to final destination
reciprocal track
180° of your track
if drift is left (WCA right) then double and subtract it from reciprocal heading
if drift is right (WCA left) then double it and add it from reciprocal heading
