NewToSki.com is reader supported. We may collect a share of sales or other compensation from the links on this page. As an Amazon Associate, we earn from qualifying purchases.
Every year skiing technology seems to advance at a quicker pace, with new and improved equipment becoming available each season. One of the most significant breakthroughs was the shift from straight to shaped skis, but what exactly is the difference?
All modern skis are considered shaped; these evolved from straight skis, which were the industry standard until the 1980s. A parabolic ski is a type of shaped ski with a much more significant sidecut, giving it the hourglass shape that is synonymous with most skis on the market today.
Modern skis don’t share the same shape as their predecessors from before the 80s. Until this time, skis were straight, the only variation in shape being their tips and tails. Straight skis have advantages, but their drawbacks make them inferior to skis today.
In the 80s, various ski companies pondered how they could make their skis easier to turn, enhancing their ability to carve through hardpacked snow and moguls. This led to experimentation with different sidecuts, which birthed the shaped ski.
In 1990 the first shaped ski hit the market, and it would set the bar for pretty much all other skis to follow. Elan immediately started producing shaped giant slalom skis, which took the sport by storm. Since then, skis have gotten shorter, wider, and stiffer to accommodate more technical and aggressive skiing styles.
What Is Sidecut?
Sidecut refers to the variation of the width of a ski between tip, waist, and tail, which is why most skis today are shaped like an hourglass. Engineers realized they could make it easier to turn by tapering the width of the ski, making the tail skinnier than the tip.
Sidecut has the added benefit of increasing the amount of edge, also known as effective edge, that comes into contact with the snow at any given time. A straight edge tends to have fewer points of contact because snow conditions are unpredictable, and no run is perfectly flat.
All parabolic skis will have a different amount of sidecut, or sidecut radius, depending on the type of ski. This means that all-mountain, freestyle, big mountain, and racing skis will all have different shapes because they are intended for different styles of skiing.
The easiest way to envision a sidecut radius is to imagine that the line created from the curve on the side of the ski continues until it forms a full circle. The radius of this circle is known as the sidecut radius, which measures how easily a ski will turn.
Most modern parabolic skis fall between a radius of 15-20m; the smaller the radius, the easier the ski will be to turn. Ski length and profile will also affect the turning radius of a ski.
Shorter radii are common in all-mountain and freestyle/park skis. All-mountain skis need to be effective no matter the snow conditions and terrain, and freestyle/park skis need to be able to edge quickly and butter every time they leave and reconnect with the snow.
Big mountain and powder skis tend to have much larger radii because they need to maintain a minimum width underfoot to handle deeper snowpacks while still being easy to turn properly.
Pros & Cons Of Parabolic Skis
Believe it or not, there are a few drawbacks to the parabolic shape of skis. Luckily, ski engineers have been able to compensate for these areas where parabolic skis are lacking. This is why there hasn’t been a resurgence of straight skis since their initial retirement.
- They are easier to turn – Sidecut allows for easier initiation of turns
- They hold an edge much better – The curved edge allows for more contact on uneven surfaces, preventing the skier from sliding out
- They are easier on the skier – Because it takes less work to turn, the skier can successfully carve without feeling prematurely worn out
- The shape allows for more specialized skis – Since the invention of the shaped ski, manufacturers have been able to create skis that will thrive in more specific conditions where straight skis did not.
- They are less stable when flat – Parabolic skis aren’t as stable when flat on the snow because they are shorter than their straight predecessors. This is more than made up for their ease of turn initiation and increased stability while on edge.
- They have more surface area and drag – A parabolic shape creates wider tips and tails, which means more friction against the snow. To combat this ski companies have incorporated rockered tips and tails to reduce contact beyond the effective edge.
- They don’t float as well – Since parabolic skis are shorter than older models of skis, they tend to sink easier in deep powder. This is why modern skis have become much wider, providing a larger surface area to stay on top of deep snow.
Are There Any Modern Skis That Aren’t Parabolic?
Not really. Though some skis seem to have much less sidecut than others they are still considered parabolic. This is exclusive to very specialized types of skis that most skiers won’t ever use.
Some slalom and giant slalom skis have much less sidecut than freestyle skis, but they are still parabolic. This results in a higher turning radius and more stability at high speeds, which is paramount considering how fast, professional racers fly down the mountain.
Cross Country Skis
Rossignol EVO Skis$503.00
Partial steel edges stop short of the tip and tail for a balance of edge control and lightweight glide.
The cross-country ski is the only other type of ski out there that has a straight shape. This is because they are used for long-distance tours on relatively flat slopes, which don’t require the skier to make hard turns at high speeds.
Thanks to the innovation of ski manufacturers in creating shaped and parabolic skis, even the most inexperienced skier can begin to feel like a pro. The evolution of ski shape has made carving much more accessible, allowing beginners to tackle more technical terrain and improve much faster.