Javelin Redesigns
On 1 April 1986, the men's javelin (800 grams (1.76 lb)) was redesigned by the governing body (the IAAF Technical Committee). They decided to change the rules for javelin construction because of the increasingly frequent flat landings and the resulting discussions and protests when these attempts were declared valid or invalid by competition judges. The world record had also crept up to a potentially dangerous level, 104.80 m (343.8 ft) by Uwe Hohn. The javelin was redesigned so that the centre of gravity was moved 4 cm (1.6 in) forward, further away from the centre of pressure (the point at which the aerodynamic forces of lift and drag act). The tip was also modified to be more blunt and less aerodynamic. All these factors combined so that the javelin had an increased downward pitching moment. This brings the nose down earlier, reducing the flight distance by around 10% but also causing the javelin to stick in the ground more consistently. In 1999, the women's javelin (600 grams (1.32 lb)) was similarly redesigned.
Modifications that manufacturers made to recover some of the lost distance, by increasing tail drag (using holes, rough paint or dimples), were outlawed at the end of 1991 and marks made using implements with such modifications removed from the record books. Seppo Räty had achieved a world record of 96.96 m (318.1 ft) in 1991 with such a design, but this record was nullified.
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