The Factors of Ball Flight free essay sample

Much of our understanding of how to manipulate the flight of the golf ball was shrouded in mystery until the early sixties when Sir Aynsley Bridgland commissioned a team of researchers under the leadership of Alistair Cochran and John Stobbs to try and unearth the secret to the game of golf. After five years of pure research the end result was certainly not what he had wished for-the secrets were that there was none, there was no such thing as the perfect swing. The work done by physicist Alistair Cochran was certainly not in vain though. In fact the findings he and his team unearthed went on to completely change how the golf professional thought about teaching the golf swing. What they discovered was that there was no secret to producing the perfect swing because it simply did not exist. There were many good, bad and indifferent swings being used but if they followed the basic laws and principles they proposed that the results would be basically the same. In this assignment we will look at many of the principles Cochran arrived at and utilize them to explain the effect a non square impact has on a golf shot. We will analyze the two of the three possible impact positions-open and closed impact positions, and how coupled with an out to in swing path can result in a variety of shots. We will also analyse how loft plays a role in effecting the degree to which shape, trajectory and distance these resulting shots go. For this assignment we will assume that the golfer is right handed, using a 5 iron of a flat hitting surface and striking the ball in the centre of the clubface. Ball flight laws Before we look at a specific type of swing path it is important to have a basic grasp of the ball flight laws as the primary focus of this piece will be the impact factors. These are entirely based on what the club head is doing at the moment it strikes the ball, known as impact. There are five impact factors, these are as follows: ? Swing Path, ? Club head Speed, ? Angle of Approach ? Clubface Aim ? Centeredness of Strike The following table explains each law in more detail Law |Characteristics | |Speed |The velocity with which the club head is travelling at | | |impact. Club head Speed effects how far the ball goes, | | |as well as the trajectory and shape of the resulting | | |shot. | |Centeredness |The exactness with which the ball makes contact on the | | |face of the club relative to the sweet spot. Contact | | |could be either on the centre, toe, and heel, above or | | |below the sweet spot. | |Path | The direction of the arc travelled by the club head in| | |the backswing an d downswing. Its line of travel at | | |impact is one of the primary factors influencing | | |direction for a full shot | | | The degree at which the leading edge of the clubface | |Face |is at right angles to the swing path. It determines the| | |accuracy of the balls flight along that line, or | | |produces a left or right curve away from that line. | |Angle of Approach | The angle formed by the arc of the clubhead on the | | |downswing in relation to the ground. Due to its | | |influence on the balls spin rate, the trajectory and | | |the distance the ball travels will be affected by this | | |angle | From these impact factors we can take nine recognised ball flights (The PGA, 2007). The illustration bellow depicts each one. For the assignment at hand we are to look at an over the top swing path with a non square impact position. In this case two-impact factors above all others influence, these are clubface position at impact and swing path. Firstly however wee will look at loft and the effects it has on the golf shot. Loft Every golf club including putters have loft. Loft is the inclination of the club face from vertical. A typical clubs loft is as follows club |loft (degrees) | |putter |0 to 6 | |driver |6 to 13 | |fairway woods |13 to 28 | |irons |17 to 49 | |wedges |49 to 64 | Loft is responsible for two primary effects. These are; †¢ It, as the name suggests, gives the ball lift and ensures the ball leaves the face at a higher angle than the angle of attack. †¢ It imparts back spin. Energy is transferred from the club head into both forward momentum and ball rotation. It is important to remember that the more loft on the club the more back spin that is imparted and the less forward momentum as a result. This is the primary reason a less lofted club will fly farther than one with more loft, in this context the shaft length is negligible. Dynamic loft It is vital to understand that the â€Å"loft† of a club and a clubs â€Å"dynamic loft† are two different entities entirely. We have previously discussed the term loft but effective loft is much much different. The effective loft is the loft a club has at impact and is determined by five primary factors-the five ball flight laws which we earlier mentioned. each of these factors,centredness of strike, club head speed, angle of approach, club face aim and the swing path all have a great bearing on the fashion by which the ball comes off the face and thus the effective loft. The following table denotes a perfect example of the effects of dynamic loft at impact [pic] as we can see from the table there is a difference of some 30 yards between the longest and shortest drive which all comes down to the dynamic loft acting on the ball at impact. This table also brings up another important point. -the angle of approach directly correlates to the trajectory of the shot. As we have mentioned earlier a higher loft results in a higher trajectory and less forward momentum but a higher angle of approach also result in a number of differences, these are †¢ The higher the angle of approach the lower the initial trajectory. †¢ The higher the angle of approach the higher the rate of spin †¢ The maximum initial height (launch angle) will be produced by presenting the maximum loft to the ball with the shallowest angle of approach. Producing the optimal angle of approach will maximise launch conditions (spin rate and launch angle) and optimise the distance the shot goes Curvature and direction As previously stated Energy is transferred from the club head into both forward momentum and ball rotation. Loft bears a great influence on how this energy is transferred into both forms. A lower loft on a club results in an increase in side spin and less backspin, for this reason a non square impact with lower lofts result in a greater curvature of the ball than that with a more lofted club. This is also the same with direction-a non square strike results in a greater range of dispersion in lower lofted club as compared to that of a more lofted club. Loft, path and face combinations In the scenario at hand we are to analyse the resultant shots from an out to in swing path, an appropriate angle of approach, 100km/h club head speed with a centred strike. And a non square impact position. In addressing these factors only two laws become a factor in the shot shape, these are 1. swing path 2. clubface aim We will now take a deeper look at the effect of each impact factor and how they effect the resulting shot shape. The Swing Path The definition of swing path is â€Å"The direction of the path immediately before, during and immediately following impact† (PGA, 2008). As the golf swing is rounded in its execution straight shots would have a swing path of inside to square to inside (Jacobs, 1979). Therefore, if it is accepted as to what swing path results in zero curvature then by introducing an out to in swing path. This is defined in the PGAs year one golf coaching study guide as â€Å"The clubheads line of travel at impact† (PGA, 2008 p 9). Jacobs (1979) agrees with Cochran et al. s he states that if the clubhead is not moving directly toward or in a straight line to your target it has to be travelling to the left or to the right of the golfers intended destination. Humans must in order to make the ball go straight, swing the club on an inside-straight-inside arc. By inside it is meant that if a line were drawn from the golf ball to the flagstick and back further behind the golf ba ll, the club would travel back inside that line to the top of the backswing and return down from inside the line to square at impact. The clubhead would then go straight through the ball at impact and follow through to the left of the line or inside as the player proceeds to the follow through position. This imaginary line will be known hereafter as the ball to target line. The next question must be then, what are the alternatives to an inside-straight-inside swing path? Firstly, if we take it that the clubface is always square to the swing path there are two possible results. The club could travel on an in-to-out swing path, which will send the golf ball to the right of the target. Conversely as in the above scenario, the club could travel on an out-to-in swing path, which will send the golf ball to the left of the desired target (Jacobs, 1979). This shot is commonly known as a pull, where the ball starts and goes in a straight line to the left of the target. Jack Nicklaus confirms this view in his 1974 book, â€Å"Golf My Way†. Nicklaus defines a pull shot as â€Å"Your clubface is looking in the same direction the clubhead is travelling. The trouble is that you are swinging from out-to-in across your target line† (Nicklaus, 1974 p25-26). He describes the push in exactly the same way except that the club is travelling from inside-to-out in relation to the ball to target line. Toski and Flick (1978) confirm this analysis of swing path. All these opinions are based on the clubface being square to the path; however it must now be asked â€Å"What would happen if the clubface were not square to the path at impact? † Clubface Condition at Impact and Initial Ball Direction To recap, the reason that the ball will travel in a straight line is that a clubface that is square to the path will impart only one type of spin on the golf ball, backspin. Cochran and Stobbs, 1968). Thus the ball will only spin vertically and stay on a straight line. However, the clubface may not be pointing at a ninety degree angle and perfectly square with the swing path. Thus if it is pointing to the left of the ninety degree angle, the clubface would be labelled as â€Å"Closed† or if it were pointing to the right of that angle the clu bface would be termed â€Å"Open† (Jacobs, 1979). These clubface positions are the vital ingredient in sidespin being imparted on the golf ball, which leads to curvature of the golf ball. Therefore, depending on the swing path along with the clubface condition at impact one of the nine common ball flights will be achieved. Initial Ball Flight Direction Toski et al. (1978) and Cochran et al. (1968) reinforce the relationship between these two laws concurring that this is what ultimately defines the initial starting direction of the ball flight. This starting point will be somewhere in between the direction of the swing path and the clubface aim. Finally they concur that the ball will begin in a direction that is closer to the clubface aim direction. Initial Ball Flight Direction [pic]= Swing Path= Face Aim = Initial Ball Flight Direction = Ball to target Line The above diagram depicts the initial flight direction on a draw shot To summarise, Jacobs (1979, p. 26) describes it very plainly â€Å"If the clubface is facing to the left of its’ path, the ball will curve to the left of that directional path. If it faces to the right of the path, the ball will curve to the right†. So for a draw shot it can be assumed that the clubface is slightly closed to the path but how exactly is it controlled and executed? The resultant shot shapes from the scenario The scenario provided can result in a myriad of shots all of which derive from the club face position at impact, these shots are as follows †¢ Square club face-the pull: the ball starts left of the target and fly’s without curvature in a straight line, finishing left of the target. †¢ Shut club face-the pull hook: the ball starts left of the target and then curves left in the air, finishing well to the left of the target †¢ Open club face-this offers two shot shapes 1. he fade: the ball starting to the left of the target and curves to the left, finishing on the target 2. the slice: the ball starts left of the target and curves to the right, finishing well to the right of the target We will now look at each of these shots in more detail The square club face: The pull As previously mentioned the pull shot is a result of a square face to an out to in swing path. The pull: the ball starts left of the target and fly’ s without curvature in straight line, finishing left of the target. This shot itself fly’s just as a straight shot but directly to the left. This shot should fly approximately the same distance as a normally struck straight shot with a normal trajectory and flight The shut club face: The pull hook The pull hook shot results in the ball start left of the target and then curves left in the air, finishing well to the left of the target. The shot itself will have a lower trajectory due to the closed club face which delofts the club at impact and as a result send the shot low to the left –the severity of which depends on how closed the face itself is to the swing path. The delofting of the club face also plays a crucial part in the over all distance travelled by the shot with a more severely shut face comes a greater loss in distance. The open club face: The fade and the slice The open faced impact with an over the top swing path throws two shot shapes which is down to relationship- of the club face to the ball to target line. In a slice the ball starts left of the target and curves to the right, finishing well to the right of the target.