Chevrons on Trailing Edge Add Power and Control
When a water ski’s tail is sliding sideways around a turn, turbulent eddies that form on the low-pressure side at the back of the fin can cause cavitation. Fin cavitation shows up as tail slides, tip-grabs and blowouts while turning at max lean angles. This phenomenon is why all standard fins have holes drilled through them. But these holes create a lot of drag and lose their effectiveness at extreme angles causing the tail to let go when grip is needed most.
Tail-grip that deminishes with increasing angle requires the standard fin to be bigger than ideal, and that it be tuned for our hardest passes. These big-fin setups make turning during easier passes more difficult than necessary, which of course is no problem for pros. Amateurs, on the other hand, struggle to perform well with most of the factory setups recommended by pro skiers. Ideally, the fin should be easy to turn during any pass, and it should retain consistent grip as lean angles get more extreme—for pros and amateurs.
The patent pending chevrons at the back of the WhisperFin PRO organize the wake behind the fin in ways that minimize cavitation and drag. And by angling the chevrons upward, the more the tail slides the more grip the fin generates, maximizing tail support when you need it most—during high-speed, tight turns caused by the late, narrow preturns of your hardest passes.
This unique trailing edge increases tail-hold so much, the fin can be run .030” to .040” shallower than the original WhisperFin. And this reduced fin area improves turn-initiation at the ball, and reduces tip-rise out of turns.
If none of this makes any sense to you, all you need to know is that this fin maintains the easy-turning quick-accelerating nature of the original WhisperFin, plus adds noticeably more consistency and composure than any other fin when pushed to extremes. The phrase most shared by testers has been, “I can’t believe what I just got away with.”
Upgraded Aluminum Improves Roll Behavior
The less the fin flexes, the more linear tail behavior is while the ski rolls in and out of turns. This is because a soft fin flexes most as it transitions through mid-roll angles, making the ski’s tail “catch” then “snap-release” as the ski rolls up onto its steepest edge where the fin unloads. Then as the ski is rolled off its edge exiting the turn, the fin catches again as it abruptly flexes in response to its increased side loading, exaggerating turn-exit wheelies.
The original WhisperFin was machined out of stiff 6061-T6 aluminum billet, a big upgrade over the usual sheet aluminum used for fins. The WhisperFin PRO has been further upgraded to aerospace grade 7075-T651 aluminum for over 50% more strength, improving tail consistency through the full roll range.
Natural and Tech Evidence Supporting Chevrons
Placing chevrons along trailing edges to achieve flow efficiencies is not a new idea. In fact, it’s the product of millions of years of evolution where survival depends on competitive advantages. Here are some examples of this competitive evolution from nature, aerospace and motors ports.
The bottom line is that this patent pending trailing edge is not a gimmick. It’s a genuine performance advancement, an advancement that good skiers feel in their harder passes, and an advancement that produced PBs right from the start of prototype testing.
WhisperFin Original vs. PRO
The choice between the original and PRO versions of the WhisperFin isn’t so much about boat speed or line lengths as it is about skiing style. Here are some factors to consider:
- Both fins benefit novice through expert skiers by making the ski easier to turn and accelerate.
- Both fins benefit advanced skiers by making it easier to keep the tip down while exiting turns.
- Regardless of line length or skill level, if you tend to approach the turn tip-high then rotate a lot of tip into the water to turn (think windshield wiper), the PRO version is far more forgiving of this technique.
- If you tend to blow the tail out of the water or to get a lot of tail slides when scrambling, go pro.
- If you turn better on one side than the other, putting a slight bend on one or more of the chevrons at the back can make a big difference to the symmetry of your skiing (a one-time modification for good skiers only).
- If your skiing inputs are smooth, progressive and controlled, the original WhisperFin can take you all the way.
- The PRO can always be mounted shallower in the ski to make it just as novice friendly as the original. But running the original deeper can’t replicate the benefits of the PRO’s improved grip at high roll angles and extreme levels of smear.
- The original is 1/3 cheaper while supplies last.