Filippi: Why The Carbon Reverse-Wing Rigger?

If ever you get the chance during an international regatta, take a moment to observe a rowing boat equipped with carbon back-wing riggers (via the help of an overhead drone shot). You’ll soon realize that the hull remains perfectly straight despite the stresses subjected to the rigger by the rower. However, this hasn’t always been the case. Thanks to significant advancements in boat-building technology, Filippi Boats enable the rower to power through the water while avoiding the S-shaped torsional rotation. This is particularly vital in sweep rowing, where torsion forces reach their highest levels.

Structures with “Distributed” Parameters

Why did this happen, we hear you ask? It’s a little something Filippi call ‘concentrated parameters’. Manufacturers used to focus on the solidity of the ribs in relation to loads produced by the riggers when in reality, the ribs essentially acted as rigid bulkheads. Under stress, sections of the boat weren’t reinforced like ribs and tended to rotate and flex.

After significant investment in software, the introduction of innovative new materials and enhanced testing capability, we can now talk about ‘distributed parameters.’ Think of the torsion of a can – if you twist both ends in opposite directions, a 45-degree line will be created, showing an uninterrupted rotation with the same angle. 

To this end, the introduction of the carbon back-wing rigger has been instrumental in accelerating the distributed parameters process (to the extent of basically being a must-have in the single scull). 

Forcing the Back-Wing

In order not to flex, the boat must react with equal and opposite force to that produced by the movement of the rigger – the increasing use of onboard cameras means we’re all familiar with this distinctive movement. In both sculling and sweep, the rower compresses the rigger and, as a result of its position behind the pin, the rigger tends to rise towards the bow and twist the boat, which creates a need to rebalance the generated torque and avoid deformation. Finite elements method software (F.E.M.) allows Filippi engineers to identify and evaluate the necessary re-balances and maximize fluid dynamic design.

There is an element of deviation between sweep and sculling pertaining to the carbon back-wing rigger. Typically, torsion derives from a technical deficiency in sculling, whereas small degrees of torsion are considered normal in the sweep. According to Filippi simulations, this corresponds to approximately 120kg per 1 meter, which is the distance between the point of application of force and the boat’s center. In such cases, partial reinforcements are not sufficient. The experience of rowing on the water, alongside this software, tells us that the boat must be stiffened along the complete length of the gunwale. As a result, Filippi have designed an area of increasing thickness of the sandwich, with targeted layers in critical positions. 

Knowledge of Materials 

Now, this is where their skills really shine through. Filippi represents the beating heart of boat-building innovation and they stand true to the values of constant refinement in pursuit of original and comprehensively-tested solutions. Where others may simply guess at the layering level within the sandwich, their superior knowledge of the raw material paired with the collection and analysis of dozens of real and computer-generated characterizations allows them to optimise their product composition choices. 

To add to this, they immediately recognized that guaranteeing the absorption capability of maximum loads (as in the case of the Italian ‘Moto Guzzi’ transverse cylinder head configuration, where the loads double on both sides) within their carbon back-wing rigger would be beneficial when considering and adhering to international rowing boat weight limits. They have also factored in multiple settings and vast amounts of setup adjustability, whereby any customer can benefit from absolute rigidity. 

Suggestions for Rowing Clubs

Occasionally, some customers ask Filippi to transform their boat built with a sculling back wing rigger into a shell suitable for sweep rowers. 

Although it is not ideal for elite-level boats (given that the layering will be markedly different), the sandwich structure that they have painstakingly developed allows for flexibility between disciplines in exceptional circumstances. However, they would still recommend focusing your choice on one specialty at a time!

Reach out to Filippi at https://www.filippiboats.com/eng/contacts

About The Author

Tom Morgan

Tom is the Founder of JRN. He has been creating content around rowing for over a decade and has been fortunate enough to witness some of the greatest athletes and races to ever grace our sport.

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