MANUAL RADAR

PLOTTING

3 Perform Manual Radar Plotting

Plotting has two main tasks:

It can show whether danger of collision exists, how close we will pass the target and how much time is left

3 Perform Manual Radar Plotting

Approximate determination of the course and speed of the other vessel, so avoiding action can be taken when needed

3 Perform Manual Radar Plotting

Vector

3.1 Construct the relative motion triangle

Vectors sum

3.1 Construct the relative motion triangle

3.1 Construct the relative motion triangle

Vectors sum

3.1 Construct the relative motion triangle

Principles of relative motion

3.1 Construct the relative motion triangle

3.1 Construct the relative motion triangle

, , , .

3.1 Construct the relative motion triangle

Plotting triangle

3.1 Construct the relative motion triangle

Plotting elements

3.2 Determine course, speed and aspect of other ships

3.3 Determine CPA and TCPA

3.4 Recognize the effect of course and speed changes

3.4 Recognize the effect of course and speed changes

3.4 Recognize the effect of course and speed changes

3.4 Recognize the effect of course and speed changes

3.4 Recognize the effect of course and speed changes

OwnDATA

T A R G E T S

A B C D

Course

Speed kts

CPA / TCPA

New CPA

New course

New speed

T man

3.5 Report radar plot data

Fixing plotting exercise data

OwnDATA

T A R G E T S

ship A B C D

125 Course

12.6 Speed kts

CPA / TCPA

New CPA

New course

New speed

T man

3.5 Report radar plot data

Fixing own ship data

OwnDATA

T A R G E T S

ship A B C D

125 Course 215 005

12.6 Speed kts 14.8 6.3

CPA / TCPA 0.2 / 14m 0.8 / 10m

New CPA 2 nm 2.2 nm

New course - -

New speed - -

T man

3.5 Report radar plot data

Fixing target plotting data

OwnDATA

T A R G E T S

ship A B C D

125 Course 215 005

12.6 Speed kts 14.8 6.3

CPA / TCPA 0.2 / 14m 0.8 / 10m

New CPA 2 nm 2.2 nm

155 New course - -

12.6 New speed - -

9 min T man - -

3.5 Report radar plot data

Fixing own ship data changes

Plotting in true motion mode

ARPA in true motion mode

246

ARPA in true motion mode

CPA

CPA

Vt Vt

Vr

Vt

Vt