Kick Precision and Spin Rate in Drop and Torpedo Punts

The drop punt delivered with a backspin is more common in Australian football, whereas the torpedo punt delivered with a rifle spin is the standard kick in rugby. The spin rate and the kick precision were measured with a smart Australian rules football, instrumented with three high speed gyros. The kick precision is defined by the elevation angle of the spin axis, with 0° and 90° being the perfect drop and torpedo punts, respectively. The data were recorded from participants of various skill levels in Australian football and rugby, kicking the ball with rifle spins and backspins. Torpedo punts were kicked at higher spin rates than drop punts (8.2 vs. 4.8 revolutions per second). The average kick precision in torpedo and drop punts was similar (80%, if the perfect kick equals 100%). There was no evidence from the recorded data that spin rate influences the kick precision.