Shane Warne's Spin Secrets Revealed

A CricInfo Exclusive Report

1 April 1998


Prof. Loof Lirpa and Dr. Heinz Bohnen, researchers into aerodymanics in Cambridge, England, have finally come up with an explanation for Shane Warne's flipper. Just like Wasim and Waqar's tricks with a swinging cricket ball, Warney has one too: reverse spin.

They have discovered that when the ball is spinning backwards around its own axis a certain number of times faster than it is travelling forward the ball will dip alarmingly. The actual ratio of spin to forward velocity abovewhich this happens turns out to be just a little under 57 - 56.86, to be precise.

Regular viewers of Australian cricket will no doubt note that Warne's flipper, as called by commentators, seems to behave a lot like a normal legspin bowler's topspinner, and, indeed, dips at the end of its flight. Now we know the reason.

Lirpa says: ``As the outer circumference of the ball passes a critical velocity, flow around the ball changes from laminar to turbulent, causing an aerodynamical change. Few bowlers have the ability to spin the ball this rapidly and retain control, which is what makes Warne unique.''

Further experiments conducted by Bohnen confirm the theory, and also reveal that this velocity is reached quicker in a less dense gas such as methane.

Prof. Lirpa revealed that he had passed on his findings to Indian test star SR Tendulkar earlier this year, and that Tendulkar had applied these findings to playing Warne, with evident success.

``He has told me that now he understands the physics behind reverse spin, he is able to spot the flipper, and predict its movement. He has also told me that he is contemplating moving to England to study this effect at first hand when he has time to pursue his sadly neglected education''.

Tendulkar could not be reached for comment or confirmation.

Contributed.


Source: A CricInfo Exclusive Report

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Date-stamped : 07 Oct1998 - 04:16