Considering the amount of media hype on modern golf equipment claiming that players can achieve unbelievable gains in distance, it is possibly time to study the real physics behind some of the claims. What is clear is that equipment is better today than it has ever been, but to suppose that by simply changing your golf ball or clubs it is possible to gain 40 to 50 yards in distance is simply not realistic.
Firstly we must examine the whole business of face deflection and those drivers that are deemed by the USGA to be "illegal". There are plenty of stories around about how players immediately gained 50yards by switching from their conforming drivers to non-conforming drivers.
Britt Lindsay - Golfsmith Director of Technical Services recently produced this insight into a fascinating subject.
The Coefficient of Restitution (COR) is a scientific ratio that measures the efficiency of the impact between the ball and the clubhead. A zero COR indicates that all the energy between the ball and the clubhead was lost in the collision and would be considered as the worst case scenario. At the other extreme, the highest rating of 1.0 COR would be considered to be a perfect impact, where all the energy of the collision is retained in the ball after impact.
If you measured the COR of the first popular stainless steel metal woods that were introduced in the 1980's, you might get a COR of 0.740, where some of the "hot" metal woods of today easily reach 0.845 COR, but for reference, the USGA limits clubheads to a maximum COR of 0.830. At 90mph clubhead speed, the difference between these two heads, all other things being equal, would be approximately 13.7 yards.
The difference in the performance of the 1980's metal wood and a modern clubhead that falls just under the USGA legal limit, say 0.815 COR, is approximately 9.8 yards.
Another factor in the quest for increasing distance has been increased clubhead speed which also affects an increase in ball speed. Longer and lighter clubs have continued to be developed in the hope that a player could generate greater clubhead speed without actually having to become stronger, or improve their technique.
Again the maths reveal that for every 1mph that we increase clubhead speed, distance could only be increased by approximately 2.8 yards. The misconception is that every player that goes to a longer and lighter club automatically sees distance increases, but looking purely at length, clubhead speeds increase only by about 0.5mph in computer models for every 1 inch increase in length. Of course all golfers are different and the results may vary, but if all golfers could swing exactly the same from one swing to another with the only exception being the club length, the maths say that the increase of one inch in length would be just 0.5mph, which equates to 1.4 yards.
Overall club weight is the other key factoring determining what swing speed a player can achieve, and it must be considered when testing longer clubs. The bottom line is that longer clubs must be lighter for most people to swing efficiently.
To examine the differences let's look at a comparison between a 43.5inch driver with an overall weight of 13.5 ounces (which was the average 25 years ago) and a 45 inch, 10.45 ounce club that could be built today. Based on the same computer model, the increase would be 8mph and, if you consider the 2.8 yards for every 1mph increase, the increase in distance is 22.4 yards. That is indeed significant, but remember that the player must be able to hit the lighter, longer club in the centre of the face in order to achieve these optimum results. These figures are of course based on one type of swing path and each person can experience different results due to the differences in their own particular swing path and speeds, from those obtained from the computer model.
These exercises help to set realistic targets on what we can expect from out equipment with regard to distance .In short you should play the longest, lightest, club that you can control, hit in the centre of the face with a face designed to deflect the maximum amount allowable.
But remember that computer models have a perfect swing and tour pros are exceptional players and when manufacturers advertise huge gains in distance it's the top pro's they are talking about.
|
