Tenders blazing new trails

Nov 22, 2022 by Erik Speyer

Mapping technology allows tenders to scout safe passageways in uncharted waters and beam hi-res seafloor images back to the bridge in real time. 

Anyone who has spent significant time on the water is familiar with the concept of depth sounders: Send a wireless signal to the bottom, wait for it to be reflected, apply some simple math, and voilà! You know the depth! It’s a far cry from the days of painstakingly dropping a line with a lead weight and measuring the distance to the seafloor. 

Today, there are many types of sounding technologies to provide mariners with seafloor mapping in real time. Such products come in all shapes and sizes, and many have become very affordable — even for a weekend warrior. One product, though, is capable of transforming a yacht tender into a powerful frontline reconnaissance tool — and that, especially for explorer yachts, can be a treasure worth its weight in gold. 

WASSP (Wide Angle Seafloor Sonar Profiling) was originally designed by Furuno company ENL for the lobster and cray fishermen of New Zealand, allowing them to produce very high-resolution mapping of the seabed, according to Rufus Whiteford, sales and marketing manager at WASSP. After the 2011 Christchurch earthquake, the seafloor had changed so much — up to 7 or 8 meters in some places — that the New Zealand navy had the fishermen map the entrance to the harbor for them. 

Impressed with the quality of the data, the navy reached out to ENL and a portable version of WASSP was created. It allowed the New Zealand navy to put a unit on a tender, do a survey of the seafloor, and beam it back to the mother ship in real time. That same technology is now available to the public, and Whiteford says the demand is quickly growing in the superyacht market. 

As exploration becomes more and more popular with superyacht owners and charter guests, vessels are looking to get off the beaten path and venture into places they’ve never been before. Some of these locations can be poorly charted, leaving captains to fend for themselves. Sending a crew member out on the tender to scout ahead and radio back the depths as the yacht carefully follows the tender is a common tactic in such situations.

Now, WASSP’s W-Series (“W” meaning wireless) allows the captain of a yacht to see — in real time — exactly what the seafloor under the tender is like while standing on the bridge of the mother ship.  As David Gratton, of Telemar Yachting Americas, explains: “Unlike other top-tier processing solutions, WASSP allows you to separate the mother ship from the tender and report the data back, potentially enabling safer navigation from a distance.”

WASSP contends that its Multibeam Sounder technology allows vessels to profile the seafloor 100 times faster than traditional single-beam echo sounders, and its real-time 3D mapping allows for a 120-degree, port-to-starboard view of the water column and seabed.

The clever part, Whiteford says, is that even if the Wi-Fi link is lost, the data is stored on the tender and becomes available once the link is reestablished. The Wi-Fi link is based on line-of-sight, but vessels can expect about 1.5 miles of range between the mother ship and the tender. 

The coverage is roughly three times the depth, so if you are in 20 feet of water, you will see a profile that is about 60 feet wide. It’s a much larger picture than simply knowing what the depth is under that tender. 

What’s more, once that data is streamed back to the mother ship, it’s saved — so the captain can then navigate off that data. This can be done in real time, or a harbor, for example, could be surveyed and that data saved for later use.  

While WASSP has its own interface, it also integrates with navigation software commonly used on yachts, such as Timezero. This not only allows captains to view the data in a navigational context with which they are familiar, but it also allows for the use of more robust computers. 

Gratton, who understands that yard time is a precious commodity, says yachts should budget at least two to three weeks for a WASSP install once parts arrive. He cautions that “the transducer being glassed in can be a large endeavor.” On the low end, a full tender-mother ship installation will run about $65,000, but each application is different, he said.

While systems like WASSP may not be the solution for every yacht program, technological innovation and growing demand have resulted in commercial-grade systems becoming more commonplace in the leisure market. They are not cheap, but these technologies could save a vessel from a catastrophic grounding, easily making up for their cost. And let’s just face it — they are fun!


Erik Speyer is Director of Sales at Bluewater Books & Charts and previously worked in the technology sector. He can be reached at [email protected]