Installation manual

Trawl hydrophone installation
93
851-165187 / Rev.A
Vertical coverage area II
Dual hydrophone installation with hydrophones different
distances from the bow, and tilted differently.
Typical tilt configuration for operation in both deep and shallow
water when hydrophones have different distances from bow.
(A) = Port hydrophone tilted 20 to 35 degrees
(B) = Starboard hydrophone tilted 10 to 20 degrees
The hydrophone closest to the main propeller should be on the
port side of the hull and have the greater tilt of the two,
approximately 20 to 35 degrees. The hydrophone on the
starboard side of the hull should be tilted approximately 10 to
20 degrees
Note: The “tilt angle” is measures from the vessel’s water-line t oward
the bottom when in operation. A vessel’s hull and keel are
normally not parallel with the water-line and/or the bow may
lift when trawling. These factors must be noted and taken into
consideration when deciding on the best possible hydrophone
configuration for a given vessel. Refer to the theoretic
penetration depth table for more information.
Hydrophones have a vertical beam width of 30 degrees and
should be tilted so with regard to optimizing system
performance at the particular trawl depth in use. This
configuration should be decided upon before hydrophone
installation commences.