The Navigation Computer

Question 1

Surface wind is -

Answer 1

Magnetic

Question 2

Finding W/V:

How to solve:

HDG 220°, TR 210°, TAS 100, GS 110. Determine W/V

Answer 2

Try and get a picture.

The heading is right of track, so wind must be coming from the right. Groundspeed higher than TAS, must be a tailwind. If you do this, it will provide an extra layer of certainty. You will be able to verify whether the answer is correct or not.

1. Set HDG under the index arrow.
2. Select TAS under centre dot
3. The drift is left, to the value of 10°, so make a pencil cross where to 10° left drift line cuts the GS 110 arc.
4. Rotate the scale until the pencil mark is on the centre line at the bottom of the computer.
5. Read the wind direction under the index arrow(332°)
6. Read the wind velocity between the centre dot and the pencil mark(21 knots).

Question 3

Finding W/V:

In order to find the wind direction and velocity the following must be known:

Answer 3

Heading, Track, GS and TAS.

Question 4

Finding track and groundspeed:

In order to find track and groundspeed, the following must be known:

Answer 4

W/V, TAS, HDG.

Question 5

Finding track and groundspeed:

How to solve:

W/V 330°/20, TAS 120, HDG 025°(T). Determine the track and groundspeed:

Answer 5

1. Rotate the scale and place the wind direction 330° under the index.
2. Mark the wind speed down from the centre dot.
3. Rotate the scale and place the HDG under the index
4. Slide the scale until the TAS is under the centre dot
5. Read the drift angle between the centre line and the pencil mark; wind is coming from the left, so the track must be the HDG plus the drift.
6. Read the groundspeed under the pencil mark.

Question 6

Finding W/V using the multiple drift method:

How to solve:

TAS 180
Heading 135°T - drift 5° right
Heading 075°T - drift 6° left
Heading 195°T - Drift 9° right

Answer 6

1. Set the TAS under the centre
2. Set heading 135° under the index and draw in the drift line - 5° right
3. Set heading 075° under the index and draw in the drift line - 6° left
4. Set heading 195° under the index and draw in the drift line - 9° right
5. Rotate the scale so that the intersection of all three drift lines is on the centre line, below the centre dot.
6. Read the wind direction under the index, and the wind speed between the centre dot and the intersection drift line.

Question 7

How to solve:

RAS 100, OAT +10°, altitude 7000ft. Determine TAS.

Answer 7

Rotate the dial until 7 000ft is lined up with +10°. Make sure it is (+) and not (-)! Without further rotating the scale, locate the RAS on the inside (time) scale, and immediately opposite on the outside scale will be the TAS -113 kts.

Question 8

How to solve:

RAS 300, pressure altitude 25 000ft, OAT -30°. Calculate TAS.

Answer 8

Calculate the TAS in the manner previously explained. The TAS is 447, which will be too high as a result of compressibility. From the compressibility correction table, extract the correction factor.

Multiply the TAS by the correction factor(should be a negative correction)

Question 9

mnemonic for finding W/V?

Answer 9

W/V

Have(hdg)

Tough (TAS)

Drift (set drift on GS arc)

Question 10

mnemonic for finding track and groundspeed?

Answer 10

Track & Groundspeed:

WD
WS
TAS

Question 11

Upper winds are in -

Answer 11

true