There is general agreement among monoskiers that outriggers assist with turn initiation, balance, and mobility. But how exactly the outriggers do that, and how long they should be creates animated debate. Much of this debate is based on personal experience and anecdotes, rather than an examination of the actual dynamics of the interconnected system of environment, monoski, outriggers, and skier.
The length of a skier’s outrigger is a great example of the Inverted U-Curve (Goldilocks Zone) concept of Too Little, Too Much, and Just-Right in terms of performance. An outrigger that is too short reduces performance. An outrigger that is too long reduces performance. There is some length of outrigger between too short and too long that is most appropriate for every skier. This length will vary from skier to skier. It will also vary depending upon the skiing environment. In fact, just as there is no perfect ski length for all skiers, uses, and environmental conditions, there is no perfect outrigger length. Simply stated, shorter outriggers are not “better” than longer outriggers, and longer outriggers are not “better” than shorter ones. Different people need different length outriggers depending upon their individual needs. This “just-right” length could also vary as their skiing ability changes over time.
Regardless of what anyone tells you, an outrigger is an assistive device that helps the skier control the Pitch, Yaw, and Roll of their ski. Where Pitch is Up/Down pointing, Yaw is Left/Right rotating, Roll is Side-to-Side tilting. These are the same three dimensional directions that are used to describe the motion of an airplane. Given that skiers are known to spend time in the air, the use of Pitch, Yaw, and Roll is appropriate. If you could completely control the Pitch, Yaw, and Roll of your ski via some other means, you would not need outriggers. For example, if an able-bodied skier holds that back of your seat, the Pitch, Yaw, and Roll of your ski is now completely controlled without outriggers. Ski poles are assistive devices that help able-bodied skiers control the Pitch, Yaw, and Roll of their skis. Ski poles are not “better” than “outriggers. Outriggers are not “better” than ski poles. It depends upon who is using them and why.
When most people think of a ski pole/outrigger assisting a turn, they are thinking that the pole/outrigger is used to initiate a Left/Right turn in terms of Yaw. What they are missing is that airplanes and monoskis don’t just Yaw left or right, they Roll (bank) and Yaw in order to turn due to centrifugal force. The same goes for bicycles, and skateboards, and many other balance-based mobility devices. The degree of Roll required for a turn is a function of the speed of the ski, the radius of the turn, whether or not the ski is carving or skidding, and other factors. Generally speaking, high speeds, shorter turning radiuses, and less skidding, require greater degrees of Roll. Therefore, the outrigger needs to assist the initiation and maintenance of both Yaw and Roll for those who need additional assistance.
If you can generate sufficient Yaw and Roll solely from the use of your body, then you don’t need the outrigger for it. The less Yaw and Roll you can internally generate, the more you need external assistance from your outrigger, and vice-versa. Broadly, the greater your disability, the more you use your outriggers. Able-bodied skiers may use a pole-plant to assist the initiation of Yaw but they use their body to generate Roll - because they can. Monoskiers with trunk control are also able to generate Roll (Yaw too) through use of their core strength. Conversely, monoskiers without trunk control must depend upon their outriggers for both initiation of Yaw and Roll, and the maintenance of Roll.
While monoskiers WITH and WITHOUT trunk control use their outriggers for initiation of Yaw, the main difference is in Roll. Those WITH trunk control can generate Roll with their internal core strength, or with outriggers, or through the use of both in combination. Therefore, all other factors being equal, they need less assistance from their outriggers. Thus, they can use shorter outriggers, and in some special circumstances, ski-poles. On the other hand, those unable to generate Roll from their body musculature, must generate Roll from their outriggers. Hence the need for longer outriggers.
Due to mechanical advantage, longer outriggers enable greater production of Roll than shorter ones. This statement is not an opinion. It is a fact. No different than the fact that a tripod with a wider base is more stable than a tripod with a narrower base due to the principals of leverage. To summarize: Monoskiers with less trunk control use longer outriggers to generate Roll than monoskiers with more trunk control. Both short and long outriggers can generate sufficient Yaw. Therefore, outrigger length has a greater effect on Roll than Yaw when turning.
It is important to note that it is possible to generate Roll forces by using Yaw to create centrifugal force via inertia. Bicyclists do this all the time to maintain balance, yet few consciously realize it. Bicycle tires don’t skid sideways like skis do. Therefore, it is much harder for a skier to use Yaw for controlling Roll. This is a complex discussion for another time.
Beginning monoskiers on relatively flat slopes still need to be able to create and generate Roll when turning. They will need less Roll since the speed is lower. If they are unable to generate sufficient Roll from either their trunk muscles or their outriggers (or both), they will likely High-Side fall. Those with minimal trunk control and insufficient upper body support are likely to engage in the dreaded Reverse-Angulation prior to the High-Side fall. For these reasons, repeated High-Side falls and Reverse-Angulation are signs for the need of longer outriggers for those with less trunk control.
In terms of skiing performance, an outrigger that is “too long” is one in which its excessive length interferes with the skier’s ability to control Pitch, Yaw, and Roll. In this case, the skier is able to generate sufficient control forces with a shorter outrigger. The shorter outrigger has the advantage of being lighter, not inadvertently “catching” on the snow, and allows for more shoulder mobility. Ideal outrigger length is a trade-off between advantages and disadvantages on an individual level. The Goldilocks Zone of outrigger length for each skier differs.
The only way to determine the proper length outrigger for you is by experimentation a/k/a trial and error. Nobody, regardless of their own personal skiing ability or instructional experience can determine the exact length that will work best for you without direct observation of your skiing performance in a variety of conditions.