Above It All
If the concept of a fully electric foiling powerboat still seems far-fetched, maybe this boat will make you reconsider.
Back in 2017, I spent a day or two riding around in one of the super-fast press boats covering the America’s Cup in Bermuda. And, as luck would have it, we happened to be on hand—and indeed, close enough to clearly hear the whooshing whir of the boat—when one of the lofty AC50 foiling catamarans hit a verified, engine-less top speed of approximately 48 knots. I can tell ya—the dramatic nature of the experience set me to immediately wondering whether foiling technology might someday be applied to production-type powerboats, given the obvious efficiency advantages entailed in waterborne cruising via foils, as opposed to the more conventional hull forms that have been around for the past 50 or 60 years.
It turns out that my thinking, wildly enough, was well behind the curve. At the very same time I was bopping around the America’s Cup course, Gustav Hasselskog, the founder of Swedish boat company Candela Speedboats, was already working with a cadre of engineers representing a variety of disciplines—aeronautics, carbon-fiber lamination, computer-based flight controllers and e-mobility—to take the foiling powerboat concept further than anyone (including yours truly) was imagining at the time.
In 2018, in an attempt to market a powerboat that would be ineffably economical to run, Hasselskog and Candela introduced the Candela Seven to the world—a fully electric, 26-foot, foiling powerboat with a reported range of 50 nautical miles (at 20 knots) and a profile that is, in my opinion, way prettier than the profiles of the few internal-combustion-driven power-foilers (including a Boeing Jetfoil) that surfaced during the 1970s and 80s and then ignominiously faded from the scene.
There’s no denying, however, that the Candela Seven is a VERY complicated vessel. In flying-over-the-water mode, with both the main amidships foil and the smaller foil at the stern (above the streamlined propeller torpedo) deployed, the boat is by all reports totally unstable, given that it is balancing its entire weight on an exceptionally small, highly efficient, drag-reducing footprint. This instability, though, is addressed by constantly and incrementally adjusting the flexible, cored-carbon-fiber main foil at a rate of about 100 times per second via a “flight computer,” accelerometers and an array of ultrasonic, barometric, gyroscopic and other sensors that keep tabs on wave height, roll, pitch, running attitude, speed and other parameters. In a sense, Candela says, the boat’s constant inclination to fall over on its side is being instantaneously and recurrently computer-corrected for virtually all conditions.
While Power & Motoryacht won’t have the opportunity to sea trial a Seven until later this year, video footage suggests that the svelte little watercraft handles the straightaways under moderate sea conditions like any other speedboat, albeit one that literally flies above the waves. Top hop is 30 knots, according to Candela. And with foils retracted while puttering along, the draft is just a bit over 2 feet, a detail that bodes well for beaching, trailering and/or lift storage. And making even sharp turns has a conventional feel to it, according to Candela’s marketing rep Mikael Mahlberg, who says he’s driven several of the 29 boats the company sold last year.
“She will bank in a very comfortable, conventional way,” he explains, “because the main foil can be twisted slightly by moving its leg-like supports both fore and aft, either together or not together, a feature that produces a slight inward roll while cornering and helps the foil-rudder-propeller assembly at the stern accomplish directionality.”
There are some other conventional details worth mentioning. For starters, the price of the boat is $250,000, a figure that certainly exceeds the high-end runabout benchmark, but not by as much as I’d expect. Moreover, much like manufacturers of internal-combustion monohull sportboats, Candela offers all kinds of options, from teak decks to underwater lighting to a variety of canvas packages. And while the Torqeedo full-electric powerplant (with a 40-kW marinized BMW i3 battery) is perhaps not exactly mainstream, the Torqeedo brand is popular enough in the United States and around the rest of the world to foreshadow reasonable service.
If the Candela Seven’s fully-electric, foiling persona has drawbacks, the biggie, I’d say, is the fact that the foils must be kept clean to function properly. This does not exactly preclude keeping the boat in the water under most conditions, but it certainly doesn’t encourage it. And then, there’s the aforementioned complexity. Yea or nay?
Frankly, at first I was personally put off by the idea of a boat that requires a flight computer to keep her charging—or rather, flying— across the briny. But once I considered the undeniable fact that passenger planes and fighter jets are zooming around reliably and safely all the time, I got just a little more comfortable with Candela’s sophisticated technology. Especially when such pluses as emissions reduction, near-silent operation, an aeronautically smooth ride and saving lots of money on fuel are factored in. Am I looking forward to sea trialing this little beauty? Oh, yeah!