underwater navigation n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Underwater Navigation PowerPoint Presentation
Download Presentation
Underwater Navigation

Loading in 2 Seconds...

play fullscreen
1 / 24

Underwater Navigation - PowerPoint PPT Presentation


  • 553 Views
  • Uploaded on

Underwater Navigation. Contents. Why use a compass ? Cardinal Points / Compass Bearings. Divers Compass. Using the Bezel. Using Compass Bearings. Turning/Using Multiple Bearings. Contents. Reciprocal Bearings. Other Considerations. Examples. Why use a Compass?.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

Underwater Navigation


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
    Presentation Transcript
    1. Underwater Navigation

    2. Contents • Why use a compass ? • Cardinal Points / Compass Bearings. • Divers Compass. • Using the Bezel. • Using Compass Bearings. • Turning/Using Multiple Bearings.

    3. Contents • Reciprocal Bearings. • Other Considerations. • Examples.

    4. Why use a Compass? • To help you get where you want to go ! • Limited field and range of vision => impossible to orient yourself underwater • Safety • Get you to shore • To keep you out of a run/current/deep water • To avoid surfacing in the “Wash”

    5. Cardinal Points / Compass Bearings • North (N) - 0 ° or 360 ° • East (E) - 90 ° • South (S) - 180 ° • West (W) - 270 ° • NE - 45 ° • SW - 225 ° • SSE - 158 ° approx • WNW - 293 ° approx

    6. Rotating Bezel Lubber Line Markings North of Needle Direction of Travel Line Diving Compass

    7. Using Compass Bearings

    8. Using Compass Bearings • Rotate compass until chosen bearing is in the viewing window • E.g. want to go NE => 45° • Keep chosen heading in the window and proceed in direction of lubber line

    9. Using the Bezel

    10. Using the Bezel • Point lubber line in desired direction. • Wait for compass to settle. • Align bezel markings with ‘N’ arrow on compass needle. • Reciprocal will be opposite compass marking. • Do not move bezel during the dive. • Set up bezel/get bearings before submerging.

    11. Reciprocal Bearings • Reciprocal bearing is the opposite bearing of a given bearing i.e. return bearing. • Allows you to return to where you started. • !NB you must allow for drift & “Kick”. • To calculate a reciprocal bearing: • Add 180 to outward bearing • If the result is >360, then subtract 360

    12. Reciprocal Bearings • Out on 90º(E) • 90 + 180 = 270 • =>return on 270º(W) Out on 90º N Back on 270º

    13. Out on 225º N Back on 45º Reciprocal Bearings • Out on 225º(SW) • 225 + 180 =405 (NB > 360) • 405 - 360 = 45 • =>return on 45º(NE)

    14. Turning/Using Multiple Bearings • Use rule of thumb: • “left is less” • To make a 90º left turn. • => subtract 90 - “left is less” • To make a 90º right turn. • => add 90 - “right is more”

    15. Turning/Using Multiple Bearings • Example 1 (turn left) • going west, turn left will point you south • 270º (W) - 90 = 180º (S) • Example 2 (turn right) • going north, turn right will point you east • 0º (N) + 90 = 90º (E)

    16. Considerations • Trust the compass - It doesn’t lie ! • Hold compass level. • Plan the dive: winds, currents, deep water • Local features e.g. sand ripples, buoy & line • Remember your bearings! • Night use - Luminous markings. • Magnetic interference.

    17. Examples • Shore Diving. • Diving an Island. • Wall Diving. • Diving a Sea Stack.

    18. Shore Dive

    19. Shore Dive

    20. Island

    21. Wall Dive

    22. Sea Stack

    23. Summary • Why, how and when to use a compass. • Cardinal Points / Compass Bearings. • Multiple bearings. • Reciprocal bearings. • Considerations. • Examples.

    24. Questions?