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Nautical navigator

Keep track of your position out at sea by obtaining a fix and using a dead reckoning.
Plan a session with this activity

You will need

  • Pens or pencils
  • Rulers
  • Compasses
  • Plotters
  • Nautical charts or maps
  • Access to a sailing vessel
  • Weather-appropriate clothing
  • Safety equipment

 

Before you begin

  • When heading out on a sea adventure it’s important to be properly prepared and stay safe. Check out yachting ahead of your sailing trip for more information about rules and permits.
  • The badge requirement involves sailing for four to six hours in one stretch. You could do this during a camp or extend your usual session.
  • Familiarise yourself with plotting positions using a dead reckoning, and plotting an observed position using different methods of obtaining a fix. Try reading this article about the eight traditional ways to find a fix, plus six more.

Get onboard

  1. The person leading the activity should explain what a dead reckoning is and how to plot an observed position by obtaining a fix.
  1. Everybody should sensibly board their boat, making sure they are wearing weather-appropriate clothing and safety equipment. Make sure everyone is prepared for at least four hours of sailing and has everything they need with them.

Get a dead reckoning

  1. To get a dead reckoning position, you need to know a starting point, a heading, and the distance travelled. Start by taking a bearing and performing any adjustments for magnetic deviation and variation to create a true heading.
  1. Turn the bezel on a compass or plotter to show the adjusted true bearing.
  2. Place the edge of the compass or plotter against your last known position on your map or chart. Line up the lines on the bezel with the grid lines on the map, making sure the north marker on the bezel points towards north on the map.
  3. Draw a line from the last known position along the edge of the compass or plotter, in the direction you have travelled. This direction will be marked on the compass with a large arrow (the direction of travel arrow).
  4. Use a ruler or dividers to mark how far you’ve travelled along the line and mark this position, along with the time you recorded it. This is your dead reckoning position.
  5. Keep up the dead reckoning by plotting the boat’s estimated position at least every hour during the sailing session.

Obtain a fix

  1. Try different ways to obtain a fix. See which works best, helping to accurately keep track of your location.
  2. At least once per hour, plot the boat’s observed position by obtaining a fix.

Reflection

This activity was about developing new skills. Modern technology often replaces older methods and techniques, and can make life a lot easier. What’s the point in learning and using traditional techniques? People could think about how modern electronics like GPS systems could break, run out of battery, or be lost over the side of a boat. Knowing how to effectively use other navigation techniques can get people out of sticky situations.

Learning traditional techniques can help people to better understand how modern methods came about and how they work. This understanding can help people to improve their skills and learn new things more quickly and effectively. This isn’t just true for sailing: lots of modern tools have replaced traditional methods. Can anyone think of other examples?

Safety

Adventure

This activity has specific rules and systems to make sure it’s managed safely. Visit the adventure page for more information.

Water games and activities

Be careful when doing activities with, in, or near water. Check surfaces and reduce the risk of slipping where possible. Make sure you have appropriate supervision for this activity.

All activities must be safely managed. Do a risk assessment and take appropriate steps to reduce risk. Always get approval for the activity and have suitable supervision and an InTouch process.