3Dplane

Thank you very much for your advise. Do you use TrackMan or any flight measuring equipment in your lessons?

I think students need to know that the more down they hit, the more "out" their actual path is relative to the swing direction. We also need to explain why that is the case. In such cases, I think it would be easier to teach if the name CP Shift was defined.

When he will use TranckMan or Flight Simulators, he should understand that Why Club Path is not same as Swing Direction. And he need to know how he can correct Club Path to the Target Line. The instructors may teach students that they need to hit down blow(negative AoA) when the ball lies on the ground(not tee up). I think it is better the instructors also teach CP shift at that time.

Thank you very muc. Now I understand that D-plane covers that the path of the club is 3D in nature and how it relates to the baseline/HSP/swing direction, and the arc on which the club is swung. So the formula between Club Path(horizontal) and AoA is also covered by D-plane, right?

D-plane is a plane consisting of club path and face angle, and the ball spin axis is approximately perpendicular to this plane and represents the direction of the ball curves. On the other hand, CPshift refers to the deviation of Club Path from Swing Direction when AoA is not zero. The amount of deviation can be calculated from AoA and Swing Plane. D-plane and CP Shift are different concepts. https://www.youtube.com/watch?v=uelExstv-no&t=14s If AoA is not Zero, ball launch is not same as swing direction. So we need to chnage swing direction in order to match the launch angle to the target line. To fix ball flight (curve) by changing the AoA is very diffucult, almost impossible.

I think this is essential information for juniors aiming to become competitive golfers.　Therefore, I think it is necessary to give it a name.　It's very strange that something so important doesn't have a name.

This is well known by golf instructors or specialints. but it is not common that it is mentioned dureing golf lessons. It may be told at the same time of the advise that ball must hit down blow at iron shots. But because it has no name. it is not be told most of the case. So it is convenient it has a name. CP shift was named by one if the golf instructor, not myself.

CP shift was not discribed in the D-Plane theory. Jorgensen did not mention even attack angle. To hit the ball straight, Face to path must be zero. (If hit at the sweet spot of the club face) So if we aim to a target with straight ball with non zero atttack angle, swing direction must be right or left to the target line along with the attack angle.

CP (club path) shift is a phenomenon in which the swing direction and the club path at impact shift when the attack angle is not zero. The amount of deviation is follows. For example, if the attack angle is -5 degrees and the swing plane is 60 degrees, it will be about 3 degrees in to out. This 3 degree angle is equivalent to 5 yards off at 100 yards. What this means is that as long as you hit with a down blow, if the swing direction is straight (parallel to the target direction), the club path at impact will be in to out, so you cannot hit a straight ball with the straight swing direction. In other words, [Can't hit a ball straight with a straight swing] If the attack angle is -5 degrees, it is impossible to hit straight ball to the target direction unless the swing direction is turned to the left by about 3 degrees. This 3 degrees mean that about 5 yards shifts at 100 yards, about 8 yards shifts at 150 yards, and about 10 yards shifts at 200 yards. If you align this line with an alignment stick and address it, you’ll feel horribly pointing to the left of the target. That’s why you can’t straighten the club path unless you turn the swing direction to the left. Of course, even if the club path is facing to the right, you can aim at the target with a draw ball by closing the face angle, but it is not easy to curve the ball and aim at the target as described later. When hitting the upper blow with a driver, on the contrary, the club path at impact will not be straight in the target direction unless the swing direction is turned to the right. For example, if the upper blow is 2 degrees and the swing plane is 50 degrees, the deviation of the club path will be about 2 degrees to the left. 2 degrees means that you’ll be off to the left by about 8 yards at 250 yards away. If you don’t turn to the right that much, the club path will not be straight. When you actually address it, you will feel that it is facing way to far right than you imagined. It should be noted that when hitting a down blow, the club head is not outside the target line before the impact, and the club head at the time of impact is the outermost. This is because the impact is when the club head is farthest from the body with the swing direction facing to the left. (See Fig. below) Similarly, in the case of upper blow, the club head does not go outside the target line after impact. (See Fig. above)