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This Crozon-born device offers a different reading of human propulsion underwater, between free swimming and assisted gliding.
Human propulsion revisited through hydrodynamics
The DeepFoil is designed for finned swimmers, freedivers and recreational divers looking to optimize their underwater movement. The wing, held in both hands, acts as a supporting surface. As the user fins, it generates hydrodynamic lift, transforming part of the vertical effort into horizontal translation.
The principle is well known in surface sailing with foils. Here, it is transposed underwater, without motor or mechanical assistance. The advantage lies in the reduction of parasitic movements and a tighter trajectory.
A simple object, but structuring design choices
The wing has a wingspan of 90 cm, is 25 cm wide and 2 cm thick. This ratio represents a compromise between lift and handling. A larger surface area would increase lift but complicate handling and transport.
The main material is HIPS plastic, chosen for its rigidity and recyclability. This choice facilitates mass production and keeps costs down. A wooden version is also available, made in Brittany with a more traditional approach.
The hydrodynamic profile is inspired by biomimicry, in particular cetacean fins. This type of geometry promotes fluid flow and limits turbulence. On the other hand, the lack of profile adjustment limits adaptation to different body sizes and swimming styles.
Between leisure accessory and technical tool
The DeepFoil is aimed at a wide audience, from coastal swimmers to occasional divers. It can be used for snorkeling, freediving or shallow exploration. The main benefit is the sensation of gliding and reduced effort over short to medium distances.
For scuba divers, the benefits are more limited. The size and simultaneous management of the equipment make its use less obvious. On the other hand, for dynamic freediving, the wing can improve the distance covered at constant effort.
But the machine does not replace conventional techniques. It is a complementary tool, with variable benefits depending on level and environment.
Industrialisation: the key to meeting demand
The development of the DeepFoil illustrates a classic pattern in lightweight boating. The first prototypes were produced using 3D printing, at a rate limited to one unit per day. Demand soon exceeded this capacity.
The move to industrial production in the Vendée region marks an important milestone. It ensures profile homogeneity and enhanced mechanical strength. For an object subjected to repeated hydrodynamic stress, this consistency is essential.
This change also raises the question of quality control and durability. HIPS offers good rigidity, but its resistance over time, particularly to UV and salt, remains a point of concern for regular users.
Priced from 95? ttc, this type of product is part of a wider trend in the boating world towards lightweight, transportable, non-motorized equipment. It's an approach that appeals to sailors looking for autonomy and simplicity, without sacrificing the sensation of gliding. In the end, DeepFoil doesn't transform diving, but it does offer another way of getting around underwater, halfway between technique and fun.
