One of the most frequent questions we get at BLL concerns the side imaging or side scan sonar coverage gap under the Humminbird SOLIX or HELIX transducer.
“Is there a gap and if so how big is it?” This can be critical to know when searching for a high value contact such as a drowning victim. BLL always recommends overlapping coverage so Zone 2 of one pass covers the gap of the adjacent pass.
The overage gap size depends on beam angle and water depth* Here are the stats
Depth (ft) Approximate Coverage Gap (ft)
If your one of the few folks experimenting with towing a Humminbird the exchange depth with towfish altitude.