Mounting a 520-5PSD transducer for use with BBDS1

[MV Mobius]

We are having a custom 24-meter aluminum powerboat built for us in Turkey. Most of the hull has integral fuel and water tanks below the waterline, so the placement of the two transducers is a bit problematic. In the aft section, just forward of the prop tunnel, we are installing an Airmar UDST800 which isn't too much of a problem as the hull is flatter back there.

Then, we are planning to install this bottom discriminating 520-5PSD plastic transducer in the forepeak area enough aft of the bow thruster to be in smooth water, but before the section where the tanks start. However, this transducer doesn't come with any fairing of its own, and the hull is very steep-sided up there, so the question is how to install this in our aluminum hull. Can we build a plastic or aluminum fairing with a recess for the transducer to sit inside to protect it and smooth out the water flow and reduce aeration? Or, do the sides of the transducer head need to be unobstructed with the transducer head protruding on its own below the hull plates? Also we are concerned that the fairing material - if we build it out of aluminum, for example - might interfere with the transducer's reception. And of course, we want the transducer to have some protection in case of a grounding.

We would appreciate any help and/or thoughts on our dilemma.

Wayne and Christine Hodgins
Blog: http://www.mobius.world

 

[Snips]

MV Mobius,
Thanks for attaching a picture of your project.
Due to the dead rise of the hull I don't see an easy way to mount the transducer that far forward without cutting into the hull an creating a pocket fairing to protect the transducer.

Snips

 

[MV Mobius]

Hi Snips,
Sorry I didn't get back to you. I read your response and got distracted with other issues with the build. Thank you for responding to my question.

We are considering welding a vertical aluminum pipe in the hull and then fairing around it on the outside to make it as aerodynamic as possible. Is that the way you are suggesting we do it?

Christine

 

[Snips]

MV Mobius,
You will need to do something like that. The 5PSD isn't a flush transducer so you probably should think of adding a little front fairing to protect it from impact. Another thought would be to use the flush mounted 520-PLD. Technically this transducer isn't Bottom Discrimination Rated but would work for normal soundings.

Snips