Driver Dynamic Loft Optimization at Different Swing Speeds

[Killa]

So I’m wondering about something regarding the dynamic loft. So if I understand correctly in ideal conditions the dynamic loft with the driver is static loft + angle of attack (let’s discard opening/closing the face at impact for now - so ideal impact conditions, so no shaft unloading as well). 
 

So if we look at the trackman carry optimizer for my range. I swing in the 105-110 range. 
 

Optimal dynamic loft at +5 AoA is 16,2° so an ideal driver loft would be 11,2° at 105mph and at 110mph the numbers are 15,2° and 10,2°. 
 

If I were hitting down on the ball with an AoA of -5° and not wanting to change that the optimal dynamic loft numbers are 11,1° and 9,9° respectively. So that would mean my driver lofts should be 16,1 and 14,9° to maximize distance while still hitting down with the driver.

 

Now let’s do the same with a lower swing speed - 90mph. At +5° AoA the dynamic loft should be 18,5° so that would mean the optimal driver would be 13,5°? So basically a 3 wood? What am I missing and why don’t they make drivers that are that high in loft if that is what it takes to optimize the carry? Ok the total optimizer might be better to use for swing speeds of 90 and lower as for that you want 15,3° dynamic loft so a 10,3° driver but isn’t the carry number more important than the total number as it is highly dependent on conditions?

[ChetlovesMer]

30 minutes ago, Killa said:

So I’m wondering about something regarding the dynamic loft. So if I understand correctly in ideal conditions the dynamic loft with the driver is static loft + angle of attack (let’s discard opening/closing the face at impact for now - so ideal impact conditions, so no shaft unloading as well). 
 

So if we look at the trackman carry optimizer for my range. I swing in the 105-110 range. 
 

Optimal dynamic loft at +5 AoA is 16,2° so an ideal driver loft would be 11,2° at 105mph and at 110mph the numbers are 15,2° and 10,2°. 
 

If I were hitting down on the ball with an AoA of -5° and not wanting to change that the optimal dynamic loft numbers are 11,1° and 9,9° respectively. So that would mean my driver lofts should be 16,1 and 14,9° to maximize distance while still hitting down with the driver.

 

Now let’s do the same with a lower swing speed - 90mph. At +5° AoA the dynamic loft should be 18,5° so that would mean the optimal driver would be 13,5°? So basically a 3 wood? What am I missing and why don’t they make drivers that are that high in loft if that is what it takes to optimize the carry? Ok the total optimizer might be better to use for swing speeds of 90 and lower as for that you want 15,3° dynamic loft so a 10,3° driver but isn’t the carry number more important than the total number as it is highly dependent on conditions?

Well... um... hm... I was told there would be no math.

[saevel25]

2 hours ago, Killa said:

So if I understand correctly in ideal conditions the dynamic loft with the driver is static loft + angle of attack (let’s discard opening/closing the face at impact for now - so ideal impact conditions, so no shaft unloading as well). 

I don’t think this is correct. I always thought it was loft presented at impact. 
 

[BC-to-MI]

1 hour ago, saevel25 said:

I don’t think this is correct. I always thought it was loft presented at impact. 
 

Yeah, this is it. Static loft and angle of attack are both factors in dynamic loft, but it's not an equation using those numbers.

What is Dynamic Loft? - TrackMan

---

The vertical angle of the club face at the center-point of contact between the club and ball at the time of maximum compression Dynamic Loft is the amount of loft on the club face at impact and is …

 

[Killa]

6 hours ago, BC-to-MI said:

Yeah, this is it. Static loft and angle of attack are both factors in dynamic loft, but it's not an equation using those numbers.

What is Dynamic Loft? - TrackMan

---

The vertical angle of the club face at the center-point of contact between the club and ball at the time of maximum compression Dynamic Loft is the amount of loft on the club face at impact and is …

 

Well yes, but the other factors are shaft flex, impact position etc. For example if you deliver your club slightly open it will be higher, and slightly closed lower, if your shaft unloads before the impact it will be higher, if your shaft is still loaded it will be lower etc... but like the best physics phd I decided to ignore that for now, as you can actually hit the ball with these factors not adding anything to the equation. 

[saevel25]

6 hours ago, Killa said:

but like the best physics phd I decided to ignore that for now, as you can actually hit the ball with these factors not adding anything to the equation. 

Very unlikely that a person would present the static loft of the driver at impact. 

Making any determination of what loft to choose is impossible. That is why club fitting is important in this regard. 

[billchao]

7 hours ago, Killa said:

Well yes, but the other factors are shaft flex, impact position etc. For example if you deliver your club slightly open it will be higher, and slightly closed lower, if your shaft unloads before the impact it will be higher, if your shaft is still loaded it will be lower etc... but like the best physics phd I decided to ignore that for now, as you can actually hit the ball with these factors not adding anything to the equation. 

It’s not a theoretical physics discussion, though. You can’t just ignore shaft kick and the amount of ulnar or radial deviation by the player at impact when discussing dynamic loft. That’s why it’s called dynamic loft.

[Killa]

17 minutes ago, billchao said:

It’s not a theoretical physics discussion, though. You can’t just ignore shaft kick and the amount of ulnar or radial deviation by the player at impact when discussing dynamic loft. That’s why it’s called dynamic loft.

Well you can assume these factors can be the same for a golfer with 75mph and a golfer with 115mph. I do get @billchaos point about the importance of club fitting to get these things correct. But I’m still wondering if there is a large group out there that would benefit from an 15°+ driver head...

[saevel25]

4 minutes ago, Killa said:

But I’m still wondering if there is a large group out there that would benefit from an 15°+ driver head...

Someone who swings very slowly. They need the dynamic loft to make up for the lack of spin rate that keeps the ball in the air. 

[billchao]

4 minutes ago, Killa said:

Well you can assume these factors can be the same for a golfer with 75mph and a golfer with 115mph.

No you can’t. A club head traveling at 115mph is going to load a shaft more than a club head traveling at 75mph.

Everyone swings differently. There’s no set rule that says all shafts add 2° of loft at impact or something.

[Killa]

4 hours ago, billchao said:

No you can’t. A club head traveling at 115mph is going to load a shaft more than a club head traveling at 75mph.

Everyone swings differently. There’s no set rule that says all shafts add 2° of loft at impact or something.

...

yet 95% of us use stock heads and shafts that “kinda” fit our swing speed. 

[iacas]

1 hour ago, Killa said:

yet 95% of us use stock heads and shafts that “kinda” fit our swing speed. 

I'm not sure what you mean there. Nothing you said there refutes what @billchao said.

[billchao]

1 hour ago, Killa said:

...

yet 95% of us use stock heads and shafts that “kinda” fit our swing speed. 

The fact that most people are doing something is not an indicator that it's the best way to do things.

There is so much more to fitting a shaft than swing speed. 

[iacas]

FWIW I have a 9.5° driver with an x-flex shaft and I tend to deliver the clubhead with about +3° AoA.

My ball launches at about 14-15°.

Almost all of that difference is the added shaft kick. It's important.

[Killa]

On 8/26/2020 at 10:44 PM, iacas said:

I'm not sure what you mean there. Nothing you said there refutes what @billchao said.

I’m saying there is a not negligible chance that the other factors contribute a small percentage in a number of people. 

On 8/26/2020 at 10:45 PM, billchao said:

The fact that most people are doing something is not an indicator that it's the best way to do things.

There is so much more to fitting a shaft than swing speed. 

I agree on everything. 

On 8/26/2020 at 11:30 PM, iacas said:

FWIW I have a 9.5° driver with an x-flex shaft and I tend to deliver the clubhead with about +3° AoA.

My ball launches at about 14-15°.

Almost all of that difference is the added shaft kick. It's important.

Looking at my last trackman session my dynamic loft was 14,7 my AoA was 3,9 my driver was 10,5. Dynamic - AoA = 10,8 in that instance. 

[RFKFREAK]

14 minutes ago, Killa said:

I’m saying there is a not negligible chance that the other factors contribute a small percentage in a number of people. 

I agree on everything. 

Looking at my last trackman session my dynamic loft was 14,7 my AoA was 3,9 my driver was 10,5. Dynamic - AoA = 10,8 in that instance. 

Now y'all are tempting me to do a trackman session just to see what my numbers are.