Williams 'skate fins' legal

(GMM) Despite the banning for 2009 of winglets and other bodywork appendages, Williams' new FW31 hit the Jerez test track on Sunday featuring the prominent 'skate fins' on the cockpit sides.

The large vertical fins are reminiscent of last year's engine cover 'horns', which because of the aerodynamic rules changes for 2009 are no longer seen on the cars.

But despite suggestions the surfboard-style Williams fins may be illegal, technical director Sam Michael explained: "In the area of the head restraint, the 75 millimeter radius (bodywork) rule does not apply."

The Australian clarified to Germany's Auto Motor und Sport that the fins are not downforce-producing, but rather "flow aids".

Michael said BMW-Sauber has already dabbled with a similar concept and that it is likely "others will follow suit".

Also evident from recent test appearances is that Toyota is staying with the so-nicknamed 'shark fin' engine cover concept for the new TF109 single seater.