Navigation

Question 1

Great circles

Answer 1

A great circle can be drawn through any two points on the earth’s surface unless the two points are at opposite ends of the diameter of the earth

Question 2

Direction

Answer 2

Is measured clockwise from north using a three figure group from 000 to 359

Question 3

Distance And Speed

Answer 3

1 minute of latitude is a distance of one nautical mile

Question 4

Because the earth is not

Answer 4

a perfect sphere then the actual length of a nautical mile has been averaged to 6080 feet which is approximately 1.85 km

Question 5

WAC chart , how it is produced

Answer 5

by projecting the surface features of a miniature earth , together with the latitude - longitude grid , onto a cone

Question 6

Parallels of latitude

Answer 6

are curves which are concave to the nearest pole

Question 7

A constant scale of

Answer 7

(1: 1 000 000)

Question 8

Magnetic variation

Answer 8

• The difference between true north as indicated by the meridians and the direction of the earth’s magnetic field is called the magnetic variation.

Question 9

Measuring magnetic variation

Answer 9

○ East is Least = subtract magnetic variation
○ West is Best = add magnetic variation

Question 10

Magnetic deviation

Answer 10

• The compass is prone to errors due to electrical and metal components of the cockpit that influence its readings.
• These errors are called deviations.

Question 11

How it is dealt with

Answer 11

• An engineer measures the deviation for the aircraft.
• The results are placed on a card which is usually placed in the cockpit near the compass to allow the pilot to apply deviation correct to various headings.

Question 12

Magnetic compass - Acceleration errors

Answer 12

If an aircraft is travelling in a north or south direction, there is no issue

When the aircraft accelerates east or west, the heavy end of the magnet will lag behind and the compass will show a movement towards the South.

When the aircraft decelerates east or west, the heavy end of the magnet will lag behind and the compass will show a movement towards the North.

Question 13

Remember, in the Southern Hemisphere

Answer 13

S - South
A - Accelerate
N - North
D - Decelerate

Question 14

Magnetic compass - Turning errors

Answer 14

O - Overshoot
N - North
U - Undershoot
S - South

Question 15

Flight Planned Track (FPT) [Can also be called Track (TR)]:

Answer 15

Is the path that the pilot intends to follow over the ground. Usually indicated by a line drawn on a chart between two locations or points.

Question 16

Groundspeed

Answer 16

• GS is the TAS adjusted for the effect of wind.

Question 17

Time interval

Answer 17

• To calculate the time interval, the navigator must know the speed of the aircraft over the ground - the GROUND SPEED [GS]

Question 18

For example TAS = 160 kt into 20 kt headwind

Answer 18

ground will be 180kts.

Question 19

1 in 60 rule , Two assumptions

Answer 19

• Assumption One
  ○ If you maintain a constant heading and a constant TAS in a constant wind, the track you make good will be a straight line.
• Assumption Two
  ○ A small change of heading will produce the same change in track made good [TMG] with no change in ground speed.

Question 20

International Standard Atmosphere

Answer 20

○ Sea level pressure in ISA is 1013 hPa
○ Sea level temperature in ISA is 15oC
○ Pressure is assumed to drop at a rate of 1hPa for each 30 feet of height INCREASE
○ Temperature is assumed to drop at a rate of 2oC for each 1000ft of height increase.

Question 21

Pressure height formula

Answer 21

Pressure Height = Elevation +30(1013 − QNH)

Question 22

Transition layer

Answer 22

• Aircraft flying above the transition altitude all have their altimeters set to 1013 hPa, regardless of the area QNH in the region they are flying.