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R&D Papers

DOL-Fin Technology:

The DOL-Fin uses high aspect ratio hydrofoil based monofin technology, which results in very efficient swimming propulsion.  (See Theory for more technical details.)  For freedivers, the DOL-Fin promotes improved depth, distance and endurance.  For SCUBA divers, the DOL-Fin provides increased speed and range while reducing physical stress to extend the diver's air supply.  The added speed makes diving in strong currents less hazardous and mild currents more enjoyable.  The DOL-Fin can provide SCUBA divers the advantages of speed and range similar to using a diver propulsion vehicle (DPV).  Unlike a DPV, the DOL-Fin has no depth limit, no batteries to recharge or replace, no electric motor to require maintenance and is extremely lightweight and easy to carry. 

  • The DOL-Fin's patented fin suspension system provides active control of the high aspect ratio fin, which provides a very natural feel over a wide speed range.  Unlike traditional monofins, the DOL-Fin system is capable of providing slow to medium swimming speeds that feel natural and that are highly efficient and not physically stressing.  This is an important capability for maximizing freediving performance.  However, there is almost no limit to the top end power that a diver can transmit through the fin.
  • The high aspect ratio fin has a custom hydrodynamic cross-section specifically designed by Smith Aerospace to operate in the oscillating lift and low Reynolds number environment of the diving fin.  The hydrofoil fin design is an integral part of DOL-Fin's active control suspension system, which maintains operation on the fin's design point over a wide range of speeds for improved efficiency.  
  • Unlike other fins, the bindings on the DOL-Fin that hold the swimmer's feet are made of textiles like a sport shoe rather than molded rubber or plastic.  This creates an adjustable, snug and comfortable fit for a wide variety of foot sizes.  Additionally, the bindings on the DOL-Fin are field replaceable so different size bindings can be used when needed.  No tools are required, and the switch takes just minutes.  With interchangeable and adjustable bindings, the DOL-Fin can be adapted to almost any diving environment.  From skin-diving in the Hawaiian tropics to dry-suit SCUBA diving in the beautiful waters off Victoria Island in British Columbia, one DOL-Fin is all you'll need.