Nav

Question 1

What is the aim of Air Navigation?

Answer 1

To guide an aircraft through the air so that it arrives SAFELY, at the RIGHT PLACE, at the RIGHT TIME.

Question 2

What 3 things lead to successful pilot-navigation?

Answer 2

1) Thorough and detailed pre-flight planning
2) A sound knowledge of Mental Dead Reckoning (MDR)
3) Accurate flying

Question 3

What is a great circle?

Answer 3

A circle on the surface of a sphere (the earth) whose radius and center are those of the sphere itself.

Question 4

What is a small circle?

Answer 4

A circle on the surface of a sphere (the earth) whose centre and radius are not those of the sphere.

Question 5

Define the equator

Answer 5

The great circle on the surface of the earth whose plane is perpendicular to the axis of rotation of the earth.

Question 6

What are meridians?

Answer 6

Semi-great circles joining the north and south pole.

Question 7

What are parallels of Lattitude?

Answer 7

Small circles on the surface of the earth whose planes are parralel to that of the equator - joining points of equal lattitude.

Question 8

What are rhumb lines?

Answer 8

A rhumb line is a regular curve on the surface of the earth that CUTS ALL MERIDIANS AT THE SAME ANGLE.

Question 9

Distance is measured in nuatical miles.

Define 1 nm.

Answer 9

The length of the arc on a great circle which subtends an angle of one minute a the centre of the earth.
Assuming the Earth to be a true sphere.

Question 10

What is the relationship between minutes and degrees?

Answer 10

60seconds=1minute, 60 minutes=1 degree

Question 11

What is variation?

Answer 11

The angular difference between the direction of true north and magnetic north at any given point.

Question 12

What are isognals?

Answer 12

Lines joining points of equal variation.

Question 13

What is deviation?

Answer 13

The angular difference between the direction of Magnetic North and that of Compass North.

Question 14

What are the 3 descriptors are used to distiguish individual maps?

Answer 14

1) Projection - the way 3D shapes have been represented in 2D
2) Scale - the size relative to the Earth
3) Topography - the nature of the detail recorded

Question 15

Define a projection

Answer 15

“A systematic laying down of the earth’s meridians and parallels onto a flat sheet in such a way that the picture displays some of the features of the actual surface.”

The way the earth’s sphere is translated to a flat sheet!

Question 16

What are the 2 types of generic projections?

Answer 16

1) Cyclindrical

2) Conical

Question 17

What is scale and what are the 3 ways to specify it on a map?

Answer 17

Scale is the ratio of distance on the map to the real distance on the ground.

1) As a ratio, e.g. 1:250,000
2) As a statement, e.g. ‘the half mil map’ = 1:500,000
3) As a pictorial graduated scale

Question 18

What is topography?

Answer 18

Topography is the detailed information recorded on the map.

Question 19

What is Earth convergence?

Answer 19

The angle that one meridian makes with another.

Convergnece = zero at the equator
Meridians converge at the poles

Question 20

What is Chart convergence?

Answer 20

The angle that one meridian makes with another ON A PROJECTION.

Question 21

What are 3 types of charts/maps used for low and medium level Nav?

Answer 21

1) 1:500,000 Low Flying Chart (LFC) - military low level nav, conical projection
2) 1:250,000 (M5219) - UK Special Air Chart for both low and medium level nav, cylindrical projection
3) 1:50,000 OS Maps - target attack planning, detailed turning point info, transverse mercator

Question 22

What chart is used for radio-aids nav?

Answer 22

The En-Route Chart (ERC)

Varrying scales

Question 23

What is the CHAD?

Answer 23

Chart Amendment Document (CHAD)
PUBLISHED EVERY 28 DAYS
-informs flying units of significant corrections to aeronautical charts other than LFCs

Question 24

What is the CALF?

Answer 24

Chart Amendment Low Flying (CALF)
PUBLISHED EVERY 28 DAYS
- lists changes to aeronautical info below 2000ft
- LFC and UK Special Air Chart ONLY

Question 25

En-route Bulletin

Answer 25

``` Corrects: -ERCs -En-route suppliments -FIH PUBLISHED EVERY 28 DAYS ```

Question 26

What are NOTAMs?

Answer 26

``` NOtice To AirMen issued frequently, allow the following amendments: 1) Obstructions 2)Danger Areas 3)Controlled AirSpace ```

Question 27

Where should a track bearing be measured?

Answer 27

Mid-track

Question 28

What are the 3 methods of expressing position?

Answer 28

1) Pin-Pointing To name the point directly beneath an aircraft's position. 2) Range and Bearing Express aircrafts range and bearing from an easily identified datum or feature. 3) Grid Reference Express aircraft's position as a point of a grid system (latitude and longitude) e.g. British National Grid

Question 29

What is lattitude and how it is measured?

Answer 29

The angular distance from the equator to a point, measured along the meridian that passes through that point. Cannot be greater than 90 degrees N or S. Given as 2 figures < 90

Question 30

What is longitude and how is it measured?

Answer 30

The shorter angular distance between the Prime Meridian and the meridian passing through the point. Expressed in degrees, minutes and seonds of arc E or W of the Prime meridian. Cannot be greater than 180 E or W Given as 3 figures < 180

Question 31

Which of the six (BNG) primary zones are over the UK (land)?

Answer 31

NO | ST

Question 32

What are the steps for map reading in CLEAR WEATHER?

Answer 32

Clock to Map to Ground

Question 33

What are the steps for map reading in CLOUDY WEATHER?

Answer 33

Ground to Clock to Map

Question 34

What are the 4 desirable characteristics of a navigation feature?

Answer 34

1) Unambiguous 2) Big (enough to be seen from the air) 3) Vertical extent for low-level nav 4) Easily identified

Question 35

What is the frequency of position checks for the tutor?

Answer 35

Time bracket of 4 - 8 minutes

Question 36

What are the 4 factors that could affect the frequency of position checks?

Answer 36

1) The availability of suitable landmarks when navigating visually 2) The availability of suitable beacons when navigating by radio aids 3) The length of the leg and the quality of the turning point 4) The need to have a safe, convenient work cycle, distributing your time between navigation, piloting the aircraft accurately and lookout.

Question 37

What are the 3 uses of single position lines?

Answer 37

1) As a check on estimated time of arrival (ETA) 2) As a check on track made good 3) As a means of homing to a landmark, turning point or target (funnel feature)

Question 38

What is the Safety Altitude a sum of? (SALT)

Answer 38

1) The elevation of the highest relevant obstacle 2) A combined safety margin for orographic errors and temperature/altimeter errors 3) A rounding up to the nearest 100ft

Question 39

What is the sector error?

Answer 39

15nm either side of track and beyond the ends of track

Question 40

What is the safety margin applied?

Answer 40

Obstacle < 3000ft - add 1000ft | Obstacle >/= 3000ft - add 2000ft