NAV Exam Revision

Question 1

What is the term used to describe the technical shape of the earth?

Answer 1

The earth is an oblate spheroid

Question 2

Name the 4 cardinal compass points and the bearing that each represents

Answer 2

North - 360/000
East - 090
South - 180
West - 270

Question 3

Define: Great circle

Answer 3

A circle on the surface of the earth whose center and radius are those of the earth
The shortest distance between any 2 points on the globe is a great circle

Question 4

Define: Small circle

Answer 4

A circle on the surface of the earth whose center and radius are not those of the earth

Question 5

Define: Rhumb line

Answer 5

A regularly curved line on the surface of the earth cutting all meridians at the same angle

Question 6

What is a parallel of latitude?

Answer 6

Circles on the surface of the earth whose planes are parallel to the equator. They are all small circles except for the equator and the equator is the zero datum for all latitude measurements

Question 7

What is a meridian of longitude?

Answer 7

Lines on the earth’s surface join the north and south pole. The zero datum for longitude measurements is Greenwich, London

Question 8

Is the equator a meridian?

Answer 8

No, the equator is a parallel of latitude and is the only great circle parallel

Question 9

List 3 ways a pilot can report their position?

Answer 9

Lat and Long
Geographical points
Line features
Bearing and distance
Reporting abeam
Estimates at future points

Question 10

What is the distance in NM for arc angles?:
1 minute of arc?
1 degree of arc?

Answer 10

1' = 1 NM
1° = 60 NM

Question 11

What are the properties of a magnet and a magnetic compass?

Answer 11

Opposite poles attract and like poles repel
Magnets attract or repel other magnets or metals that can be magnetised
If freely suspended then a magnet will align itself with the earth’s magnetic field

Question 12

Define: Nautical mile (verbatim)

Answer 12

The length of the arc of a great circle which subtends an angle of one minute at the centre of the earth

Question 13

Define: Magnetic heading

Answer 13

True heading with magnetic variation applied

Question 14

Which map scales provide greater detail?

Answer 14

The smaller the ratio of the map the greater the detail

Question 15

List the ways relief can be shown on a topographical map?

Answer 15

Contours
Spot elevations
Layer tinting
Hachuring
Hill shading

Question 16

Name 3 types of basic map projections

Answer 16

Cylindrical
Conical
Plane

Question 17

What are the 2 most commonly used projections for maps and charts?

Answer 17

Mercator

Lambert

Question 18

Define: True heading

Answer 18

A heading in relation to true north

Question 19

Define: Compass heading

Answer 19

Magnetic heading with correction to compass error

Question 20

What is drift?

Answer 20

The angular difference between the heading of an aircraft and its track

Question 21

What is UTC?

Answer 21

UTC is Coordinated Universal Time which is based on the atomic clock where each second is corrected for errors

Question 22

How many minutes of time are there in?:
1° of arc
15° of arc
180° of arc

Answer 22

1° = 4 minutes
15° = 60 minutes
180° = 12 hours

Question 23

How do you convert degrees into hours and minutes of time?

Answer 23

Degrees x 4 = minutes of time

Question 24

Conversion of local time to UTC time

Answer 24

For NZ local time:

UTC + 12 or 13 hours depending on time of year to account for daylight savings time

Question 25

Define: Civil twilight

Answer 25

When the sun's centre reaches a point 6° below the horizon

Question 26

What are the properties of a wave?

Answer 26

Amplitude - Height of the wave Frequency - The number of cycles a wave completes in 1 second Wavelength - Distance between complete cycles of a wave

Question 27

What is modulation?

Answer 27

The process of adding audio frequencies to a radio frequency carrier wave enables it to carry information

Question 28

What is a carrier wave?

Answer 28

A continuous wave being produced at a constant amplitude

Question 29

What are the 2 main types of modulation?

Answer 29

``` Amplitude Modulation (AM) Frequency Modulation (FM) ```

Question 30

What are the properties of HF, VHF and UHF?

Answer 30

``` HF = 3-30MHz, used for point-to-point communication VHF = 30-300MHz, experience very little refraction by any ionised layers and thus require a direct line of sight UHF = 300-3000MHz ```

Question 31

What is the atmospheric layer that affects radio propagation?

Answer 31

The Ionosphere

Question 32

What is the minimum equipment needed on board an aircraft for VDF to work?

Answer 32

Two way radio communication equipment operating on the correct frequency

Question 33

Define: Ground wave

Answer 33

A wave that follows the earth's surface contour

Question 34

Define: Space wave

Answer 34

High-frequency waves that do not get refracted by the atmosphere and travel into space

Question 35

Define: Skip zone

Answer 35

The area in which no signals are received, extending from the point at which ground waves become too weak to be received to the point at which the first sky wave has returned to the surface of the earth.

Question 36

What is an NDB?

Answer 36

Non-directional beacon LF-MF Long Range

Question 37

What is a VOR?

Answer 37

Very High Frequency Omni-directional Range VHF 360 radials

Question 38

What is an ADF?

Answer 38

Automatic direction-finding radio receiver | Can be tuned to an NDB to determine the direction of the beacon relative to the aircraft

Question 39

What is the angular accuracy of NDBs and VORs?

Answer 39

``` NDB = ±10° VOR = ±5° ```

Question 40

What is the cone of ambiguity?

Answer 40

NDBs and VORs cannot transmit vertically therefore there is a cone above the beacons at ~45° from the vertical where no signal will be detected from the beacons

Question 41

What is a DME?

Answer 41

A short-range navigational aid, normally paired with a VOR that provides distance and ground speed information with a range of 200NM

Question 42

Describe slant range?

Answer 42

The distance measured to an aircraft describing both the horizontal and vertical components

Question 43

What are the components of an ILS?

Answer 43

Localiser Glide path Markers

Question 44

What is the recommended glide path for an ILS?

Answer 44

3°

Question 45

What is the decision height and RVR for the ILS categories?

Answer 45

``` CAT I ILS = 200ft, 800m CAT II ILS = 100ft, 400m CAT IIIA ILS = 0ft, 200m CATIIIB ILS = 0ft, 50m CAT IIIC ILS = 0ft, 0m ```

Question 46

How does INS work?

Answer 46

Measures an aircraft's location using accelerometers and gyroscopes Detects motion and can pinpoint where an aircraft has travelled based on its known starting point

Question 47

How many different satellites are required for GPS?

Answer 47

4 (3)

Question 48

What is differential GPS?

Answer 48

By using a fixed ground receiver as a reference point an aircraft's position can be very accurately calculated by error checking its location with the fixed point

Question 49

Name the components of an SSR system

Answer 49

Interrogator | Transponder

Question 50

This frequency is used for?: | UHF

Answer 50

``` RADAR DME ILS GPS Military communications ```

Question 51

This frequency is used for?: | VHF

Answer 51

VOR | Civil communications

Question 52

This frequency is used for?: | HF

Answer 52

Long range communications

Question 53

This frequency is used for?: | MF-LF

Answer 53

NDB

Question 54

What is the track error formula for the 1 in 60 rule?

Answer 54

TE = (Distance off track x 60)/Distance flown

Question 55

What is the correction angle formula for the 1 in 60 rule?

Answer 55

CA = (Distance off track x 60)/Distance to go