Position Fixing Methods

Question 1

What types of position fixing method can you use?

Answer 1

• GPS fix
• Three-point fix
• Transit
• Depth contour
• Verticle Sextant angle
• Running fix
• Radar fix
• Sector lights

Question 2

How do you plot a running fix?

Answer 2

1. Taking a bearing of a fixed object and plot this on the chart, make a note of your course and speed
2. After some time (could be 10, 12, 15, 20 mins) take another bearing of the same object and plot this on the chart. You now have two bearing lines
3. Anywhere on your 1st bearing line plot your course steered
4. Now work out your distance travelled (S x T) and plot this on your course steered line
5. So you have a 1st bearing line, 2nd bearing line, course steered line and the distance you travelled (from bearing line one to bearing line two) marked on your course steered line
6. Using a parallel rule, transfer your 1st bearing line up to where you marked off your distance travelled. Where the 1st bearing line and 2nd bearing line intersect is your position