Sonar tube fairings for high speed vessels
Today, many CH270 hull tubes have to be placed in the forward part of the vessel. This location almost guarantees underway turbulence. Although a poor location, space limitations usually make it the only site available for the hull tube and hoist. As the installation manual shows, the best loca- tion is always one third to one half way back from the bow. This is okay, because a bit of prior planning and on - site fabrication will allow a very successful installation on a fast, planing hull vessel.When the vessel's bow rises or she is on a plane, you must prevent the hull tube rear wall from becoming a large water scoop. A simple but effective fairing must be constructed. The fairing routes (diverts) the water flow away from the tube opening, preventing it from striking the tube's rear wall. The same principles applicable for bow thruster installations are true for any sonar hull tube.
Properly sized and shaped, the fairing will minimize turbulence and destructive soundome or shaft movement. Some vessels may require several fairing size and shape adjustments to be absolutely successful. Pictures of several typical, successful fairings are attached for your information and use. A carefully fitted installation will insure you many years of reliable, trouble free CH270 sonar oper- ation.
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