Distance or Accuracy - Why not Both?
by Eric Cook. P.Eng. GSEM. PCS.

As published in Flagstick Magazine

Most golfers are looking for more distance and accuracy particularly with their driver. What is the probability that you will find clubs that can deliver both distance and directional accuracy in either off-the-rack or custom fitted clubs and what are the elements that affect club performance the most? Years of testing and research have proven that the shaft is the most important part of the club if directional accuracy is to be maintained and that, to a lessor degree, the shaft performance relates to distance.

The last few years have seen the introduction of the custom fitting trend in golf club assembly by most of the major club manufacturers. In most cases, there are many questions that they ask the customers which are supposed to help them better fit the clubs to the individual. The customers are often asked if they are more interested in distance or accuracy with their new clubs, but seldom does anyone suggest that they can provide both. I can only surmise that this approach is based on the traditional belief that stiff shafts produce better direction while softer shafts produce better distance. To some degree this concept is true. The other misconception that pervades the golf industry is the idea that shaft stiffness is in some way related to club head speed. It is usually stated that the faster you swing the stiffer the shaft should be, and the stiffer the shaft becomes, the higher the swing weight you should use. This suggests that club head weight is in some way related to shaft stiffness. Keeping these concepts in mind, let us look at the elements of the golf swing and golf clubs that affect distance and direction the most starting with distance.

The distance that you get when you hit a golf ball is directly related to the club head speed that you generate and the weight of the head that you are swinging, as well as the face angle and the trajectory of the ball as it leaves the club face. The energy that you create with a golf club is equal to the product of half the club head weight times the square of the speed or ½ MV^2, which means that club head speed at impact is much more important than head weight. The other point that you must understand is that club head speed is affected by head weight. For maximum effective clubhead speed, the head weight must be related to the speed so that you are swinging the heaviest head that you can swing the fastest. This combination of head weight and speed will produce the maximum possible energy for your swing.

The results from testing hundreds of golfers over the years were used to produce the chart, shown in Figure 1, which relates swing weight to club head speed. As you can see, since swing weight is directly related to head weight, the club head has to be lighter as the club head speed increases. No one that we have tested has ever selected a swing weight higher that D0 so why does the industry keep making men’s clubs in the D1 to D3 range? As I said earlier, club head speed is much more important than head weight because too much head weight can cause you to lose speed. Considering the fact that in the energy formula it takes 10 grams of weight to make up for the loss of one mile per hour in speed, it should be obvious that you cannot afford to lose any amount of speed because of excess head weight.

The speed that you generate during your swing is a function of how you swing. Are you a hitter or a swinger? Normally swingers create more speed with less effort because they use their body rather than their arms as the hitter does. This is a whole other subject which I may tackle later if anyone is interested in understanding the difference. For now let us understand that to obtain maximum distance you must create the maximum club head speed that you are capable of. If you can understand and improve your swing mechanics that produce club head speed, you should be able to improve your distance.

Now lets look at those elements of your swing and your clubs that relate to accuracy. It is a well established fact that the wrong shaft in any club, especially your driver, can make a difference of 10 to 30 or more yards in the direction that the ball will fly. To provide accuracy, the shaft of the club must fit the way you swing or you must learn to adjust your ball position and motion to make each club in your set work. There is no doubt that shaft flex is the element of a golf club which creates most accuracy problems for the average golfer. If the shaft stiffness is properly fitted to the golfer’s swing the accuracy of the hits will be much more consistent. If the shaft is too stiff the golfer will usually push the ball away from the target line but in some cases a slice may result depending on the person’s swing plane. The real danger, from your point of view, is getting a shaft that is too soft for your swing because even a robot that we used to verify our club testing system could not hit consistent shots with a shaft that is too soft.

While the shaft stiffness is the single most important element of the golf club as it relates to accuracy, ball position and head weight also influence accuracy. If you are to be accurate in where you hit the ball you must find the correct ball position for each club in your bag and then make sure that the ball is always put in the proper place during your setup. If you are using the normal gradient matched golf clubs where the shafts get stiffer as they get shorter, the ball should be moved back in your stance as your clubs get shorter. If the shaft stiffness was consistent throughout your set of clubs you would be able to play all of your fairway shots from the same ball position regardless of the club being used. The head weight of the clubs must be correctly matched to your swing speed if you are to maintain accuracy. If the heads are too heavy, you will probably push most of your shots while a head that is too light will normally cause you to pull the ball.

In summary, I would suggest that distance is affected more by club head weight and swing speed for the reasons explained above while accuracy depends mostly on the shaft stiffness of your clubs. I can easily verify that in almost all cases the golf industry makes Iron shafts too stiff, Wood shafts too soft and club heads too heavy for most golfers. Is there any wonder then why you cannot find a set of normal clubs that will give you both distance and accuracy?