Instruments / Gauges

[son_of_a_sailor3]

On a 21 ft catamaran how would you install a depth finder/ speed odometer? Do they make a wireless ones i just dont know how this will work if one hull is out of the water?

[Waterway Guide]

Hi SonOfASailor:
Neither would work when that hull is out of the water. I think you'd be best off with a little gps chartplotter, which would show and record your true speed and would have the charts to keep you away from shoals. That's what I used with my Windrider Trimaran.

[Jon Hacking]

Originally Posted by son_of_a_sailor3

On a 21 ft catamaran how would you install a depth finder/ speed odometer? Do they make a wireless ones? I just don't know how this will work if one hull is out of the water.

The only way I can think of to reliably get depth or speed-through-the-water on a boat that can fly a hull is to have sensors in both hulls or have a sensor pod that you can move to the downwind hull. Another possible option is to build a sensor-pod that is always in the water, between the hulls, but now we're getting really klugy...

[Factor]

Hand held GPS and hand held sounder

[son_of_a_sailor3]

yes maybe a Handheld is better, but i thought someone told me there is a wireless dept instrument , but maybe just knowing the waters i am in too helps.. thanks

[Ziggy]

Even a "wireless" transducer needs to get power somehow, so they're not really wireless.

B&G H3000 system has a provision for using two speed transducers. I'm not sure about the depth.

It would seem that a 21' catamaran would need only a few inches of water to float--do you really need a depthfinder? As others have suggested, a handheld chartplotter with charts for your area may be all you need.

[son_of_a_sailor3]

well i have 2 dagger boards that drop almost 4 ft. but i guess if i am coming into shore i would just pull both up! but it would be nice if i go to a lake that i dont know the waters having a depth gauge would be some what a benefit i guess.. I know if i am moving at 15knts i am sure i dont want to hit anything!