questions from me about the D-plane (and new fun facts by Brian Manzella on p.3)

[SteveT]

One would have to agree with this. Doesn't necessarily make the D-plane laws wrong though as this can be factored into the measurement of True Path and Face by Trackbaby, if they are being measured and not extrapolated by using an equation.

The D-plane is not a "law", it's a geometric and dynamic construct based on vector measurements.

Do the distances not depend on the combination of the various angular speeds (club, shoulders, arms)? On a lighter note, have you factored body weight into your calculations.

No, it's strictly a simplified trigonometric approximation ... sin a = a ... or for very small arc angles, the distance along the swing path is the same as the degree number.

Down plane?

Nope ... try again ... what does the "D" in D-plane stand for ..??

 

[SteveT]

Because it was "D"escriptive of where the ball started.

Correct ... and as Jorgensen wrote in Physics of Golf:

"We shall call this plane the D plane because it is descriptive of the collision between the clubhead and the ball."

Now if everybody read the Physics of Golf, all the confusion over D-plane would dissolve ...

 

[duckjr78]

Correct ... and as Jorgensen wrote in Physics of Golf:

"We shall call this plane the D plane because it is descriptive of the collision between the clubhead and the ball."

Now if everybody read the Physics of Golf, all the confusion over D-plane would dissolve ...

Not necessarily. I have had my copy of Physics of Golf for 10+ years and I am still digesting it and figuring it out. It's not written very well. That is what makes this site so good. People on this site are pushing the envelope for new and better ways to explain things in understandable terms instead on leaning on unintelligible gibberish for the sake of sounding intelligent.

 

[Kevin Shields]

Correct ... and as Jorgensen wrote in Physics of Golf:

"We shall call this plane the D plane because it is descriptive of the collision between the clubhead and the ball."

Now if everybody read the Physics of Golf, all the confusion over D-plane would dissolve ...

His defintion is a bit incomplete.

 

[SteveT]

His defintion is a bit incomplete.

How so ..??

 

[duckjr78]

His defintion is a bit incomplete.

I'd say that is being a bit generous.

 

[wulsy]

No, it's strictly a simplified trigonometric approximation ... sin a = a ... or for very small arc angles, the distance along the swing path is the same as the degree number.

But this will be influenced by the lateral movement of the centres, and the length of the radii, which are influencing the circular movement, no?

By D-plane law I meant the results of the construct based on the geometric and physical measurements: I stand corrected, it is not a law.

 

[wulsy]

The whole D-plane theory stands or falls by what is being measured and when (relative to low point and outermost point) and by what is being extrapolated. Brian was hitting from a mat in his video therefore there was no true low/outermost point which could have been measured. Trackman must have "assumed" a low point based on the other factors.

As I understand it, Trackman and Flightscope measure not only certain impact factors but also the entire ball flight, including spin. Therefore any discrepancies in what one would expect from the impact data and observed ball flight in relation to the D-plane theory are essential factors in proving or disproving the degree of validity of the D-plane theory. So the only people who can truly comment on the validity of the D-plane theory are those who have done this comparison and who are clear about what is being measured and when.

Jorgensen (and Kelley) are liable to human error like everyone else so having read The Physics of Golf does nothing more than give an insight into the theory and how it arose and will not eradicate D-plane confusion and dispute unfortunately. However I will study it when it arrives.

 

[dbl]

Wulsy, you have doubts? Trackman has several newletters out. Have you read them? If not, start there.

 

[dbl]

eradicate D-plane confusion

Whose?

Or do you mean something else like, flaw?

Personally I see little confusion expressed by people absorbing the data and theory.

 

[natep]

Link to Trackman newsletters:

TrackMan - Media

 

[bax1865]

Yes, if you're being exact.

Imagine a Ferris wheel on the target line hitting a ball to the target.

A normal ferris wheel has a VSP of 90*. No left or right bias in the up or down.

Now tip the ferris wheel 45* towards the golfer. (VSP is 45*).

You can see that for every degree the "carriage" is going down, it is also going 1 degree to the right (outward) as well.

And after the ferris wheel bottoms out, it is going 1* left for every degree up.

Therefore if it is going 5* up, it is actually going 5* left of the so called Swing Direction (the direction at lowpoint).

Now you have a face and true path 5* left of the Swing Direction. Bam - straight shot at the target.

Savy

Great answer!!!.....really good image for me to relate to. Thank You!

Now I to assume any change in VSP to any degree other than 45* will affect the 1:1 relationship?

 

[Brian Manzella]

Damn man.

The whole D-plane theory stands or falls by what is being measured....

Not even close!

The ball don't lie.

I KNEW from teaching BEFORE ANYONE TALKED ABOUT THE D-PLANE, how left you HAD TO SWING to make the ball fly straight.

I didn't need video, or TrackMan to see what was FACT.

I am going to say this one more time so you better all listen:

TrackMan, FlightScope, the new $100,000+ machine that just came out, the 3D cameras that Callaway has....

None of it changes this simple fact:

You can't swing straight down a plane aligned at the target, hit a shot off of the ground, and make the ball fly straight.

That's the friggin' ticket here, science guys.

The D-Plane BLOWS UP 600 years of bullturds.

All the other stuff is important, but that one is the DEAL maker/breaker, and makes people lose their minds and say stuff like the D-Plane is "compensation golf."

Both Steve T and Wulsy need to watch about 10 different kinds of lessons with me using TrackMan, they'd stop all of this BS.

The damn clubface normal is FIGURED INTO THE D-PLANE for the 1000000th time Steve T.

Jorgensen (and Kelley) are liable to human error like everyone else so having read The Physics of Golf does nothing more than give an insight into the theory and how it arose and will not eradicate D-plane confusion and dispute unfortunately. However I will study it when it arrives.

Man, please don't confuse those two guys.

The D-Plane is NOT A THEORY.

THERE IS NO D-PLANE CONFUSION ON THIS SITE EXPECT THE confusion you are try to cause.

Whose?

Or do you mean something else like, flaw?

Personally I see little confusion expressed by people absorbing the data and theory.

Friggin' A.

Damn.

 

[SteveT]

Both Steve T and Wulsy need to watch about 10 different kinds of lessons with me using TrackMan, they'd stop all of this BS.

The damn clubface normal is FIGURED INTO THE D-PLANE for the 1000000th time Steve T.

Hey, BManz ... you got that right .... practical application of TrackMan in lessons is a winner and you know it..!!!

 

[savydan]

Savy

Great answer!!!.....really good image for me to relate to. Thank You!

Now I to assume any change in VSP to any degree other than 45* will affect the 1:1 relationship?

You got it.

At a VSP of 63* the the clubhead is going right a 1/2 a degree for every degree down.

At a VSP of 27* the clubhead is going right 2 degrees for every degree down, etc, etc.

So, for example, at a VSP of 63*, with an AoA of -4* down, you need to swing 2* left of the target line (with a face square to the target, or 2* open to the "swing path", same thing) to hit it straight at the target with no curve, etc. The true path, and the face, will, therefore, be going straight at the target.

IMO...this is just me talking...but I thing it's true....when you hit an iron off the ground...you have to hit what feels like a little cut shot....aim a little left...swing a little left....with a face a little open to the swing direction.....so the true path and face are actually going to the target.

 

[SteveT]

So, for example, at a VSP of 63*, with an AoA of -4* down, you need to swing 2* left of the target line (with a face square to the target, or 2* open to the "swing path", same thing) to hit it straight at the target with no curve, etc. The true path, and the face, will, therefore, be going straight at the target.

IMO...this is just me talking...but I thing it's true....when you hit an iron off the ground...you have to hit what feels like a little cut shot....aim a little left...swing a little left....with a face a little open to the swing direction.....so the true path and face are actually going to the target.

What happens if your irons have an offset leading edge ... surely this changes the swing path relationship.

I have a steep wedge swing, and keep my swing path aimed at the target. Perhaps the club offset compensates for the swing path.

 

[savydan]

If you have a relatively high negative AoA with a wedge, you probably tend to have a relatively high VSP which would offset the rightward bias in your downward.

 

[SteveT]

If you have a relatively high negative AoA with a wedge, you probably tend to have a relatively high VSP which would offset the rightward bias in your downward.

Not really ... because I don't take a deep divot. I only nip the ball and brush the grass ahead of the ball for a slight AoA.

Perhaps I am so close to the bottom of the swing arc, my swing path and club normal vector line up near vertically.

Wedge trajectory is quite high and drops nearly straight down landing angle. Works for me .. except on windy days and hard greens where the ball can bounce terribly high ...lol

 

[natep]

SteveT,

Since your hitting the ball with a very shallow AoA, you are also swinging less right. If you hit the ball at the very bottom of the arc you would have no aiming compensations at all and could aim right at the target.

When I found out about the d-plane it didnt change the way I play a standard shot much at all. I was already hitting straight balls. It did make me realize that after I aimed my clubface at the target I was subconsciously wiggling everything a little left during my setup (for an iron). Perhaps you too already subconsciously make all your compensations just from experience beating balls.

Where the d-plane knowledge REALLY helped me out was on recovery shots around trees, etc. In the past I relied upon the old ballflight laws to attempt my heroic hooks and slices around trouble, and they always set me up for epic failure. Now I can figure out the d-plane for these extreme shots and pull them off with a high rate of success. I actually enjoy hitting into trouble now to see what kind of crazy shot I can pull off.

 

[wulsy]

Thanks for the link natep

Both Steve T and Wulsy need to watch about 10 different kinds of lessons with me using TrackMan, they'd stop all of this BS.

When could I take a lesson and maybe watch a few lessons? Is it warm in NO in January?