Page 28 - Electronic Navigation Cyber Book

SPEED ERROR

The speed of the recorder motor must be proportional to the velocity of
sound in seawater and the velocity is known to vary. The recorder motor
running at an incorrect speed causes the speed error. If the motor speed
is too fast, it will record a greater depth and if it is too slow than a lesser
depth.
Other errors include Pythagoras error, error due to mal-adjustment,

Checks on echo sounders

Twice yearly with hand lead, if reading is too high, the motor is going too
fast.

© 2018 Digital Galaxy Index 28