Dreher Elliptical Sculls featuring elliptical shaft profiles are offered with three distinct blade designs: Our Elliptical Aerodynamic (EA) blade shape, our Elliptical Hydrodynamic (EH) blade shape, and (the newest blade shape) our Elliptical Round (ER). All the sculls are offered in both our standard modulus and our distinctive high modulus/twill construction. High modulus sculls are indicated with the additional letter “X” in their description. All three designs incorporate a traditional roll wrapped shaft that transitions from a standard circular shape at the handle end to an elliptical shape as the shaft approaches the blade. This transition to an elliptical shape significantly reduces the impact of drag while the oar is on the recovery and moving at maximum velocity. Drag due to airflow around an elliptical shape is significantly reduced compared to a circular shape at maximum oar plus boat velocity.
Elliptical Hydrodynamic (EH/EH-X): Hydrodynamic theory plus prior racing blade performance models inspired the high aspect ratio design of our Elliptical Hydrodynamic sculls. The blade shape is narrowest by the blade/shaft interface and then increases in surface area and width towards the tip of the blade. By optimizing the aspect ratio of the blade design, we have been able to create a blade that maximizes the resolved propelling force on the blade during the drive phase and minimizes the air drag on the recovery phase resulting in a cleaner and smoother stroke.
Elliptical Aerodynamic (EA/EA-X): This oar design resembles a traditional hatchet shape, but has been modified to optimize aerodynamic advantages. If you have used traditional hatchet shaped blades in the past, you will find our Elliptical Aerodynamic sculls maintain a similar feel with the added benefits of reduced drag on the feather of the recovery. If you have mastered a late square before the catch you could see a speed increase if you can release the blades cleanly and not drag the blades on the surface during the recovery.
Elliptical Round (ER/ER-X): This oar design has the shape of a similar blade to our Apex-R or Apex-RE but has been modified to fit on our aerodynamic shaft. Because of its smaller blade-area, it is the absolute cleanest releasing blade on the market. If you have not mastered a clean release this blade shape will help. The rounded edges not only help clean up your finish, but the coupling of aerodynamic shape and blade shape provides the opportunity to gain more speed on the recovery where every boat achieves its peak speed. Our seamless blade-to-shaft transition helps to achieve a cleaner extraction at the release creating less turbulence in the water. If you have used Macons, Apex-R, ApexRE, or the EH blades in the past, you should find an enhanced sculling experience with our Elliptical Rounds.
Our Tool-Free Adjustment system is offered on all adjustable-length sculls. This feature is an additional option that allows for quick on the water adjustments. This “tool-free” load adjustment feature allows anyone to adjust the load anytime and anywhere without tools. The carbon segmented screw piece is permanently bonded to the scull shaft. The easily replaceable bearing surface is moved by a nut, with 1 cm of inboard/outboard movement for every 360 degrees turn of the nut. This easy adjustment feature allows the rower to have a better feel for which rig is correct for each wind condition. A change of the rig takes no more than one to two to three minutes to complete the four adjustments required for each set of sculls and can be accomplished easily on-the-water or on the dock.