VFR Navigation Flashcards
What is pilotage?
Navigation by reference to visible landmarks or checkpoints.
What is dead reckoning?
Navigation by means of computations based on time, distance, airspeed, and direction.
What are the 3 aeronautical charts used by VFR pilots?
Sectional, VFR Terminal Area, and World Aeronautical.
What is the scale of sectional charts?
1:500,000. 1 inch = 8 SM.
How often are sectional charts revised?
Semiannually, except for some areas outside the conterminous US, where they are revised annually.
What is the scale of VFR terminal area charts?
1:250,000. 1 inch = 4 SM.
How often are VFR terminal area charts revised?
Semiannually, except for several Alaskan and Caribbean charts.
What is the scale of world aeronautical charts?
1:1,000,000. 1 inch = 16 SM.
How often are world aeronautical charts revised?
Annually, except several Alaskan charts and the Mexican/Caribbean charts which are revised every 2 years.
Between what latitudes are the conterminous US states located?
25° and 49° N latitude.
Between what longitudes are the conterminous US states located?
67° and 125° W longitude.
How many degrees does the earth rotate through in 1 hour?
15°.
Mountain Standard Time is ZULU minus what?
7 hours.
Mountain Daylight Time is ZULU minus what?
6 hours.
When is Daylight Savings Time in effect?
Between the second Sunday in March and the first Sunday in November.
Why is course measurement taken at a midpoint near the meridian of a course, rather than at the departure or arrival points?
Because meridians converge toward the poles.
What is true course?
The course direction measured by reference to a meridian or true north. The direction of intended flight as measured in degrees clockwise from true north to the port side of the plane.
What is true heading?
True course ± wind correction angle.
What is magnetic variation, or declination?
The angle between true north and magnetic north.
How is magnetic variation expressed?
As east variation or west variation, depending upon whether magnetic north is to the east or west of true north.
How far is the north magnetic pole from the true north pole?
About 1,300 miles.
Is the Earth uniformly magnetized?
No.
What is an isogonic line?
A line which connects points of equal magnetic variation.
What is an agonic line?
A line connecting points at which there is no variation between true north and magnetic north.
On the west coast of the US, the compass needle points ____ of true north.
East.
On the east coast of the US, the compass needle points ____ of true north.
West.
What three elements impact true course?
Magnetic variation, compass deviation, and wind correction.
Where does the agonic line run in the US?
From the Great Lakes to Florida.
What is a magnetic course?
A course that compensates for magnetic variation.
What is a compass course?
A course that compensates for compass deviation.
What is magnetic deviation?
A magnetic compass error caused by local magnetic fields in the aircraft.
If the magnetic variation is west, do you add or subtract?
Add. East is least (subtract), west is best (add).
If a variation is shown as “9° E”, for a true course of 360°, what is the magnetic heading?
Magnetic heading is 351°.
How can deviation vary for different headings in the same aircraft?
For example, if magnetism in the engine attracts the north end of the compass, there would be no effect when the plane is on a heading of magnetic north.
What is the procedure for checking an aircraft’s deviation called?
Swinging the compass.
Describe, in four steps, how an aircraft’s deviation is checked.
- The aircraft is placed on a magnetic compass rose, the engine started, electrical devices normally used are turned on.
- The aircraft is aligned with magnetic north indicated on the compass rose, and the reading shown on the compass is recorded on a deviation card. The aircraft is then aligned at 30° intervals, and each reading is recorded.
- If the aircraft is to be flown at night, the lights are turned on and any significant changes are noted.
- A deviation card is mounted near the compass, showing the addition or subtraction required to correct for deviation at various headings, usually at intervals of 30°.
What is oscillation error?
The combination of all the other compass errors, which results in the compass card swinging back and forth around the heading being flown.
What is magnetic dip?
A vertical attraction between a compass needle and the magnetic poles. The closer the aircraft is to a pole, the more severe the effect.
What is track?
The actual path an aircraft takes over the ground. It is a combination of the motion of the aircraft and the motion of the air.
What is drift angle?
The angle between the heading and the track.
What method is used to determine compass heading?
CH = TC ± WCA ± V ± D
Measure true course (TC), then apply wind correction, to result in true heading (TH). Then, TH ± variation (V) = magnetic heading (MH) ± deviation (D) = compass heading (CH).
What is WCA?
Wind correction angle – the angle required to fly into the wind to maintain track.
How is wind correction angle expressed?
In degrees right or left of the true course.
How do you determine time in flight?
Distance divided by ground speed (D ÷ GS).
How do you determine distance flown in a given time?
Ground speed multiplied by time (GS x T).
How do you determine ground speed?
Distance divided by time (D ÷ T).
How many feet are in one nautical mile?
6,076.
How do you convert knots to miles per hour?
Multiply speed in knots by 1.15.
For a flight of 400 NM, at a GS of 100 knots, in an aircraft that burns 5 gallons an hour, how much fuel is required?
20.
What is a plotter?
A protractor combined with a ruler, used to determine true course and measure distance.
What is a wind triangle?
A graphic explanation of the effect of wind upon flight.
What three factors can be determined by the wind triangle?
Groundspeed, heading, and time for flight.
What are the 11 steps in obtaining flight navigation information?
TC WCA TH Variation MH Deviation Compass heading Total distance GS ETE Fuel burn rate
If wind is from the right, is WCA added or subtracted to TC?
Added.
If the isogonic line is to the east of TH, is the variation added or subtracted?
Subtracted.
When in level cruising flight more than 3,000 feet AGL, on a magnetic course of zero degrees through 179 degrees, at what altitude should you fly?
Any odd thousand MSL altitude plus 500 feet (3,500, 5,500, 7,500, etc.).
