product code: 85004.240096
Features
- Recommended with S185 or S215 Stabilizer
- Low stall speed
- Effortless pumping
- Surf-style turning (smooth rail to rail and surf yaw snap)
- Composed glide
Materials
- Pre-Preg Carbon
- Titanium Screws
Front Wing, Cover, Screw Pack D (M8x25mm)
Progress faster
The SF-Wings are easy to pump but still manageable to roll from rail to rail. The area-distribution across the span is tuned to the rolling ability of the wingEffortless pumping
The foil is super forgiving on angle of attack change – when you’re about to stall, give it one pump, then you're back in the game.Composed glide
The SF can be compared to our highly efficient HA Front Wings – only with a much lower speed range.Responsive turning
We’ve moved the wing back on the fuselage for a better turning response, so you may need to move the mast further forward in the mast track compared to other North wings.Match with S215 Stabilizer
Because the SF front wings operate at such low speed without stalling, you need a stabilizer that does the same.Progress faster
The SF-Wings are easy to pump but still manageable to roll from rail to rail. The area-distribution across the span is tuned to the rolling ability of the wing - less area in the tips helps the foil to roll with lower force from side to side. For a foil to roll, it must push the water above it out of the way – less area in the tips requires a lower rolling moment/less force. The moderate anhedral front view combines with a gently swept outline to create a good balance of roll stability, for confidence during pumping and take-offs, and manoeuvrability, for initiating turns with ease.
Effortless pumping
The foil is super forgiving on angle of attack change – when you’re about to stall, give it one pump, then you're back in the game. Because it’s so forgiving, you can take out a much smaller surf wing size than you’d expect (for wing surfing). This is appealing if you’re trying to perfect your turns and wave riding. You’re carving with a smaller foil which is more responsive. To maintain such a low pumping speed, we needed to generate more lift out of the foil section at low speeds. We always try to balance lift v drag – so to find that compromise here, we shifted the peak in the lift-to-drag ratio to the lower end of the speed range. Having more profile thickness and curvature in the front section of the profile makes it less sensitive to angle of attack changes.
Composed glide
The SF can be compared to our highly efficient HA Front Wings – only with a much lower speed range. Our Sonar HA Series has a phenomenal glide at medium to high speed – we’ve engineered the same glide into the lower-speed SF-Front Wings. Their aspect ratio ranges from 7.1 (SF1230) to 8.8 (SF930). This can be considered medium-high, however because of the evolved foil section, the stall speed is remarkably low. They can deliver that frictionless sensation of glide at a much lower speed.
Responsive turning
We’ve moved the wing back on the fuselage for a better turning response, so you may need to move the mast further forward in the mast track compared to other North wings. Mounting the front wing closer to the mast reduces your yaw stability, so you can initiate turns more easily.
Match with S215 Stabilizer
Because the SF front wings operate at such low speed without stalling, you need a stabilizer that does the same. With smaller front wings, you want to upgrade to a smaller stab, but it’s important to match the stall speed. The S215 was created with lower stall speed to complement that of the SF front wings. Advanced riders who are seeking a looser feel may choose to remove the wingtips, using the dashed guideline graphic, to create a completely flat stabilizer with a 205cm2 area.
BEHIND THE DESIGN
SONAR SF SERIES
Discover what low-speed glide and surf-style performance bring to your ride with North Foil Designer Uli Sommerlatt and Brand Director Mike Raper.
PRONE FOIL SETUP