Marine Navigation 1 - Transits & Depths

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Using natural transits to identify positions in a small boat. Using leadlines to record depth at those points. Using radios to communicate these points ashore.


Boat, radio and leadline.


1. Brief scouts on lake 'Golden Rules'. Ensure all scouts are wearing buoyancy aids that fit and are secured.
2. Brief scouts on 2 positions on marine lake - Points AA and BB. Discuss with scouts what a transit ( two objects that line up on a bearing) is and the key benefit that it requires no compass, gyro or GPS to navigate with them. Explain also how they can be used as a gyro/compass check.
3. Leave pontoon and show scouts what a transit physically looks like when on track and when to port/starboard of track. Reverse course and show that they can also be used as a stern mark.
4. Show scouts how 2 transits can be used together to pinpoint a position. Show pilotage technique of using a transit ahead to follow a course, and a transit on the beam to define a point on that line. Remind them that boats can not stop quickly, show the scouts how far throttle needs to be reduced or astern power applied to come to a rest in position.
5. In a safe position, show scouts what a lead line is, and how it is marked out. Discuss with scouts why the depth and the sea bottom material is important to mariners. What makes the best anchor-holding ground? Describe how to take leadline sounding from the bow, with the coxswain ensuring that the drive is in neutral.
6. Repeat pilotage into positions marked on aerial photo - let scouts take leadline soundings. Report these soundings ashore using the script in the attached docment.
7. Return to jetty to swap groups as necessary to make sure all members of the patrol get a go afloat.


  • Marine
  • Navigator sea
  • radio
  • seamanship

Badge Links

  • Basic Nautical - Water depth
  • Communicator - Send/Receive
  • Navigator - Transit bearing