Mistral’s VRTS

Variable Rocker Trim System Taking the sport into the comfort zone

  • The VRTS technology, is a fully incorporated trim-system fixed to the board.
  • The carbon plate is attached by a series of brass screw fitting.
  • Plate extends beyond the end of the primary hull thereby encouraging much improved release.
  • It’s function is primarily related to the trimming of the boards angle of travel.
  • Many benefits manifest from the flexible nature of the plate.
  • The degree of flex and travel of the plate is adjusted through a thumb twist adjuster.
Key features and benefits over conventional rigid tail boards.
  • Adjustable tail rocker.
  • Adjust the board’s trim to keep it more parallel to the water line.
  • Improves optimum angle of plane.
  • Micro-adjust the board’s angle of trim.
  • Adjust to differing body weights.
  • Adjust according to different wind strengths to optimise trim.
  • Adjust according to different sea states for comfort and control.
  • Early planing encourage by fine tuning tail rocker.
  • Continuous board rocker promotes improved angle of attack.
  • Upwind performance is improved.
  • Smoother ride results from shock-absorbing qualities of the plate.
  • Tail-walking is eliminated.
  • Roaster-tails flattened out.
  • Skim over bumps rather than smacking into them.
  • Board and body enjoy a smoother ride.
  • Extended planing time.
  • Cavitation reduced as the flex-plate extends beyond the fin box and the end of the board.
  • Flexing (tensioning) and release (relaxing) of the plate improves consistency of laminar flow.
  • Gybing smoothness improved.
  • Gybing control improved.
  • Straight line speed and control improved.
  • Wind off the adjuster to soften the ride, increase control.
  • Wind on the adjuster to reduce pitch angle of the hull and lessen rocker, promote early planing.
  • Permits adjustment to suit the rider to improve performance, control and enjoyment.
  • Better by design over former concepts - even over our Challenge Flex of the late 1980s (below).
Underside tail section showing bevelled area, connection points for the carbon plate and central hole for fitment of adjuster.


Plate simply slides in place and is secured with screws. Winding off the screw in lighter winds, will permit the flex-tail to compress and spring back to shape over a great range of travel, acting as a shock-absorber, while also reducing the wettedsurface area, without fear of loss of control.

As wind strengths increase, tensioning of the screw downward, to either be in contact or just off from the plate, helps negate increased pitch (angle) of the hull as the board rollsback onto the tail as the nose rises with increasing speeds, increased footpressure and lift generated through force acting on the sail. As the plate flexes, it will meet the screw and its travel will be stopped. Tensioning the screw therefore, lessens the rocker line almost to neutral if you wish, encouraging early planing times and reduces incidents of stalling, so as the angle of attack remains optimum.