What The Golf Ball Asks

Ed Mitchell, PGA
Mitchell Golf Equipment Company
May 2012

You may be aware that the collision of the club head with a stationary golf ball happens in approximately a millisecond. The implied laws of physics from this collision are either achieved or overcome with the result determining the flight of the golf ball.

We must remember that as the golfer swings, the club head tries to square and sole itself, ideally resulting in a perfect impact position to launch the golf ball. But of course, this does not generally happen 100% of the time. As a matter of fact it seldom happens perfectly. That is why golf is a game of a degree of misses and not of perfect shots.

So what does a golf ball ask from a golf club head at impact?

  • How Fast Is The Club Head Moving (Speed)
  • Where Is The Impact Point (Centeredness)
  • What Direction Is The Club Head Moving (Path)
  • What Direction Is The Face Pointing (Face)
  • Descending Or Ascending Arc Of Club Head (Angle Of Approach)

These five questions are answered through physics. They determine the Ball Flight Laws, which were identified in the PGA Teaching Manual as a result of the study from the book In Search Of The Perfect Swing.

These Five Ball Flight Laws are:

  1. Speed – The velocity with which the club head is traveling, Speed influences the distance the ball will be propelled, as well as the trajectory and shape of the resulting shot.
  2. Centeredness – The exactness with which the ball makes contact on the face of the club relative to the percussion point or “sweet spot”. Contact could be either on the center, fore (toe), aft (heel), above or below that “sweet spot”.
  3. Path – The direction of the arc described by the club head in its travel away from and then back toward the target. Its line of travel at impact is one of the primary factors influencing direction for a full shot.
  4. Face – The degree at which the leading edge of the club’s face is at right angles to the swing path. It will determine the accuracy of the ball’s flight along that line, or produce a left or right curve away from that line.
  5. Angle of Approach – The angle formed by the descending or ascending arc of the club head on the forward swing in relation to the slope of the ground. Due to its influence on the ball’s spin rate, the trajectory and the distance the ball travels will be affected.

The PGA Teaching Manual also identified 14 Principles that apply to these laws. The last being:

IMPACT – Principle #14
“There is only one moment of truth in the swing. Impact! The club’s face must be squared at this moment while the path is to the target if the ball is to travel there. It is the moment when the maximum speed should be reached and the center of the club face is contacting the ball from the desired angle.”

Since the publishing of the PGA Teaching Manual in 1990, technology has given golf industry professionals more insight into these laws of physics. What has been learned is Law #4 Face has a third dimension in play, that being “face attitude”. This is commonly referred to as lie angle, but the effect it has on ball flight is important in determining the initial direction the ball starts, along with face angle and club head path.

I propose the term “face attitude” should be added to the Ball Flight Law #4 description. Impact determines the “Tilt Axis Spin” of the golf ball, which is largely due to “face attitude”. Tilt axis spin is the initial axis the ball rotates on. It also determines the curvature of the ball flight.

Whether its through golf instruction or club fitting the same objective is sought for the golfer, a desired ball flight. So the question remains, is this objective achieved through golf instruction, club fitting or does it take both?

Can a person learn to swing any golf club and produce a certain result? Yes. So we have to ask ourselves, is it the chicken or the egg theory? Should we have a custom fit set of clubs first or should we develop a golf swing using a club that allows for swing development?

Less we forget golf is a game. The level at which we succeed in scoring is the result of a developmental process which must include golf equipment as part of the equation. Fitting equipment for impact is necessary for improvement and can be an ever-changing requirement as the golfer’s swing skills develop.