Errors of Echo Sounder?

    Errors of Echo Sounder?

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    Echo Sounder Errors
     

    • Propagation Error: The Velocity Of Sound Increases When Temperature, Pressure & Salinity Increase. Due To High Salinity In Red Sea, Depths To Be Increased By 5%.
    • Aeration: Caused By Bubbles In The Water Due To:
    1. V/L Going Astern.
    2. Moving Rudder Hard Over.
    3. Air Pockets Left Over By Bad Weather.
    4. Breaking Water Over Shoal.

                Air Bubbles Reflect The Sound Waves Resulting In False Echoes.

    • Multiple Echoes: In Shallow Waters Echoes May Be Received From The First, Second & Third Reflections From The Sea Bed. Correct Echo Is The First One, Second & Third To Be Ignored.
    • Pythagorus Error: This Error Occurs If The V/L Has Two Transducers, One A Transmitter & The Other A Receiver. Distance Travelled By Sound Is More Than Actual Depth Of Water Below Keel. More Pronounced In Shallow Waters.
    • False Bottom Echoes: This Occurs In Deep Waters When An Echo May Be Received After The Stylus Has Completed One Rotation & Begun Another.

     

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    Staff September 2, 2014

     

    • Propagation Error: The Velocity Of Sound Increases When Temperature, Pressure & Salinity Increase. Due To High Salinity In Red Sea, Depths To Be Increased By 5%.
    • Aeration: Caused By Bubbles In The Water Due To:
    1. V/L Going Astern.
    2. Moving Rudder Hard Over.
    3. Air Pockets Left Over By Bad Weather.
    4. Breaking Water Over Shoal.

                Air Bubbles Reflect The Sound Waves Resulting In False Echoes.

    • Multiple Echoes: In Shallow Waters Echoes May Be Received From The First, Second & Third Reflections From The Sea Bed. Correct Echo Is The First One, Second & Third To Be Ignored.
    • Pythagorus Error: This Error Occurs If The V/L Has Two Transducers, One A Transmitter & The Other A Receiver. Distance Travelled By Sound Is More Than Actual Depth Of Water Below Keel. More Pronounced In Shallow Waters.
    • False Bottom Echoes: This Occurs In Deep Waters When An Echo May Be Received After The Stylus Has Completed One Rotation & Begun Another.

     

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