Any ardent racquet collector is likely to have heard the name Siegfried Kuebler. Before designing tennis racquets, this German engineer used to work on rockets, namely the Sidewinder missile and various other aerospace projects, thus becoming familiar with high-tech materials. tenniswarehouse.com reports: "The first Kuebler racquets were made from extruded aluminum in 1972. Later came the development of the first mass-produced midsize racquet, followed by 100% graphite racquets in 1980. Kuebler's most renowned racquet design lead to the most famous of widebody racquets, the Wilson Profile. The Wilson Profile was predated by Kuebler's own "Kuebler Resonanz" racquet of 1985. Kuebler's goal in racquet design was to produce a racquet stiff enough to return to its original state before the ball left the strings. While just about every racquet loses energy on impact because it is still flexed when the ball leaves the strings, Kuebler realized a racquet which snapped back before the ball left the strings would actually provide significantly more propulsion into a shot."
The "Kuebler Resonanz" back then was the racquet with the by far broadest frame profile, measuring four centimeters - about 1.6 centimeters were common with regular racquets! So the Resonanz racquet constituted the new racquet category "widebody". This innovation did not come as a surprise, as Kuebler had always successfully strived to present superlatives: The "Ultra Light" racquet was the lightest racquet of its time on the market, the "Easy Play" the hardest oversize racquet.
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