Facts and Distance

[JohnV]

The USGA has just published a scientific paper on their website that shows that the ball does NOT get "super-sized" at higher swing speeds.

Please read: http://www.usga.org/news/2006/april/distance.html

Balls don't even exhibit straight-line gains as the swing speed increases because the COR of the driver goes down as swing speed increases and while lift increases as ball speed goes up, drag increases even faster.

Glad to see the Laws of Physics still apply.

[Pete Lavallee]

John, I don't deny the validity of the results using just one driver; the USGA test club. Do you think that graph's slope would change if they optimized the driver as they increased club head speed?

[JohnV]

In a word, no.

Certainly the measured distances would probably change between drivers at the same speeds, but they would exhibit the same general trends.  The COR would continue to go down as speed increased as has been shown in the papers cited (dating back to 1994).  The lift and drag numbers are based on launching the ball using their Indoor Test Range, not a driver so those numbers would stay the same.

I'm not a physicist, but I did stay at a Holiday Inn Express a few months ago.

[JohnV]

One interesting thing I've seen in the paper is that when they launched balls under optimal conditions, the distance increase due to optimization at 125 mph (7.5 yards) was a lot less than the distance increase at 90 mph (19 yards).

This can be looked at in two ways.  One is that it is a good thing because it means that optimization doesn't do as much for the big hitter.  The other is that it is a bad thing since the big hitter seems to get the results regardless of how optimal his swing/club is.

[Garland Bayley]

John,

I have a bridge in Brooklyn I am sure you would be interested in buying!

You may notice that the "scientific" paper is published on their website, not in a peer reviewed journal. Geoff Schackelford has questioned their use of the year 2000 in their arguments. The claim in the paper is that most players were using the wound balata covered ball in 2000. However, I did not have to look far to find the following on the Titleist website. "There was instant tour acceptance and near overnight conversion to multi-component urethane elastomer golf ball technology in 2000."

I don't doubt their formula and computation of results from physical laws. I do believe they misrepresent the question. The question is not whether higher swing speeds cause current balls to go disproportioniately longer than slower swing speeds. The question is the gain from the conversion of balls is disproportionately larger. It seems to me that they do a poor job in considering old vs. new balls in light of the conflict in when the new balls were put into play.

[Garland Bayley]

Well I guess I should have gone a little farther then I did on the Titleist website.
They later give a graph that is hard to read accurately, but seems to show only 27% using solid balls at the beginning of 2000, and slightly over 40% by the end.

Still Geoff's suggestion of using 1995 would clearly be comparing all wound vs. the all solid 2005.

[JohnV]

Garland, for a number of years, there have been people on this site and elseware arguing that the ball went disproportionately longer when you swung faster.  That is what this test disproves.

Please tell me what paper, whether published in a scientific journal or not, shows any facts that support that argument or counter the arguments put forward in this paper.

I don't need no bridges in Brooklyn, I live in the city of bridges.

The headline on the article is "Do Long Hitters Get An Unfair Benefit?", not does the ball go further today.

Certainly the ball goes further than a wound balata ball did in previous years.  Also, the club heads are bigger, the swing speeds are much faster, the shafts add more and, while I know that Geoff likes to mock it, the players in general are in a hell of a lot better shape.  Add it all up and I agree that golf today is a different game than 20 or 30 years ago.  Should it be changed?  In my opinion it probably should, but I'm not sure that rolling back the ball is the answer, but I've been back and forth on that a number of times.

[Garland Bayley]

John,

I think I showed you "facts" (at least what you get from a marketing website (Titleist)) that call into question the old ball vs. new ball argument of the paper.

As I wrote before, I understand what their test disproves and have no disagreement with it. I think the issue is the change in balls. I think that what drives people to conclude disproportionality is not within the same ball, but the gains derived from changing balls.

Slower swingers have always imparted less spin on the ball. The difference in spin rate between hitting the two different kinds of balls for a slow swinger is less than the difference in the spin rate between hitting the two different kinds of balls for a fast swinger. Logically, this would suggest more gain for the faster swinger. If spin rate were the only factor in play, it would demonstrate there has to be more gain for the faster swinger.

They have the science and the formulae. Why don't the plug data from the balata wound ball into their formulae and give us that result, instead of using tour data from a year of questionable ball use?

[Matt MacIver]

In that I'm no scientist (nor have I spent any time lately in a certain hotel), I have no clue if this is a reasonable question or not, but here it goes:

Doesn't acceleration have something to do with balls going further for faster swing speeds?  

It seems logical to me that a club moving at 90 mph at impact imparts x_mph force to the ball....which allows it to decelerate over y-distance.  So a club moving at 120 mph would be accelerating more through impact, thus the ball would have more imparted force and would take longer to decelerate, and stop.  Thereby travelling longer.  

I'm missing something from 9th grade physics here, what is it?  Thanks.

[Garland Bayley]

Matt,

What have to be able to do is to understand the terms used above. Since the COR goes down for higher swing speeds, the answer to your question is no it doesn't get extra kick, it gets less kick than one would expect for the higher swing speed. COR measures the rebound ability of the ball.

[George Pazin]

Matt -

You're confusing acceleration and velocity. They're not the same.

Garland -

Where do you get that COR goes down as speed goes up? Is that in the paper? (In case you're wondering, this is an honest question, not a leading question.)

[Garland Bayley]

Yep George, in the paper.

[George Pazin]

Thanks, Garland, I just read the USGA summary, maybe I'll get a chance to read the paper over the weekend.

I'm a little confused at your position. Whether one class of player, or one type of player, benefits more from a switch from wound to solid is of little consequence to me. The corollary to this would be that, for many years, the higher swing speed player would have been unduely penalized, relatively speaking, prior to the switch.

I place a lot of stock in JohnV's opinion, but I tend to fall more on the rollback side. The way I see it, even if things are maxed out now, the ball is still "causing" older courses to be stretched and modified too much, imho.

[Craig Sweet]

Didn't the Consumer Report on golf balls show the same result...slower swing speeds got as much distance, if not more, than higher swing speeds?

Here's the thing...comparing today's data with data from 5,10,20,or 50 years ago is meaningless.

What matters is what is happening now....today's ball and today's club...

From what I see at my golf course, 50% of the golfers might have clubs purchased in the last two years....and very few use Pro V1's...perhaps that is why I don't see that many golfers knockin' it 300 yards  

[Garland Bayley]

...The corollary to this would be that, for many years, the higher swing speed player would have been unduely penalized, relatively speaking, prior to the switch....

That would be from the beginning of golf that "the higher swing speed player would have been unduely penalized".

Until the modern ball, there has been nothing that changed the ball spin from a naturally occuring spin linearly proportional to the clubface angle. The modern ball changes this to artificially limited with respect to low clubface angle (and perhaps enhanced with respect to high clubface angle).

So you see, the higher swing player has never been unduely penalized. I believe that he now has been unduely rewarded by modifications to the physical response of the ball.

[A.G._Crockett]

Garland,
I don't think anybody disputes that the "changeover" from balata to solid core balls has really benefitted the pros more than the rest of us, simply because they now use balls that meet the ODS, which has been the same for years.  Most golfers were already using solid core balls before the ProV came out, of course.  Since the pros are now hitting the equivalent of a Pinnacle (almost) that spins a lot off a wedge, they have clearly benefitted the most from that change.  I think that's a settled matter, and I doubt anybody would bother to do any research on it.

As JohnV says, the issue here has been the debate over whether or not ProV's and the like give more than a 10% gain for a 10% increase in swing speed if the swing speed is very high, but only 10% or less if the swing speed is slower.  I had that impression, along with many others, and it now is evident to me that I was wrong.  The fact that 10% of a bigger number is a bigger number is NOT a nonlinear gain, so I stand corrected.

[Brent Hutto]

I'm not supposed to post on non-GCA topics but I've read the study that John linked to and here is its bottom line...

Just like everyone in the industry has always known, as clubhead speed increases the ball speed and total distance increases but at an ever-diminishing rate. So going from 100mph to 101mph buys you more additional distance than going from 120mph to 121mph all else being equal (this was shown in the USGA study to hold at least over the range 90mph-125mph).

So all the people who've been repeating that "exponential" claim can just stop (not that they ever knew what the hell "exponential" meant anyway). Basically, this study refutes the straw-man argument that beyond some mythical high clubhead speed the rate of distance increase is more than linear. Note well: this study says absolutely nothing about whether good players hit the ball too far now or whether a rollback of the ball specification is a valid way to address the distance increases observed over the past several year. It just points out and confirms the obvious which is that the same downward-curving clubhead speed versus distance relationship that has always obtained is still evident at high clubhead speeds with modern "Tour" balls. I'll admit that after years of hearing the hype I had started to wonder if indeed the manufacturers had made an end-run around that principle but now it is clear that they have not.

[Brent Hutto]

Since the pros are now hitting the equivalent of a Pinnacle (almost) that spins a lot off a wedge, they have clearly benefitted the most from that change.  I think that's a settled matter, and I doubt anybody would bother to do any research on it.

Exactly. The manufacturers found a way to make a ball that elite players can use which goes every bit as far as the ODS allows and with managable driver spin. The USGA assumed that the strongest players would always choose a Balata ball and only weaker players would max out the distance possible with their clubhead speed. When that ceased to be the case (circa 1999) it took the USGA 5+ years to react to that manifestly evident trend. I have confidence that the USGA can at least limit future distance gains and perhaps even impose a modest rollback. If that is needed, it would be better to do it now rather than wait another half a decade.

[Garland Bayley]

Garland,
I don't think anybody disputes that the "changeover" from balata to solid core balls has really benefitted the pros more than the rest of us, simply because they now use balls that meet the ODS, which has been the same for years.  

They have disputed whether that was fair. TEP called it ultimately fair and I disagreee. Eventually he called me nasty names. I wear that as a badge of honor!

As JohnV says, the issue here has been the debate over whether or not ProV's and the like give more than a 10% gain for a 10% increase in swing speed if the swing speed is very high, but only 10% or less if the swing speed is slower.  I had that impression, along with many others, and it now is evident to me that I was wrong.  The fact that 10% of a bigger number is a bigger number is NOT a nonlinear gain, so I stand corrected.

That is one issue here. And is settled as far as I am concerned.
Another issue here is does the pros benefiting from this change hurt golf.
Several subissues
a) Courses become longer
b) golf becomes more expensive
c) time to play becomes longer
d) pro game is all a boring game of smash and wedge
...
Another issue that the USGA paper did a shoddy job of addressing is did the high swing speed pros gain more than the low swing speed pros.
Subissues
Distance
Flight curvature

[Jeff Fortson]

Garland, for a number of years, there have been people on this site and elseware arguing that the ball went disproportionately longer when you swung faster.  That is what this test disproves.

Please tell me what paper, whether published in a scientific journal or not, shows any facts that support that argument or counter the arguments put forward in this paper.

I don't need no bridges in Brooklyn, I live in the city of bridges.

The headline on the article is "Do Long Hitters Get An Unfair Benefit?", not does the ball go further today.

Certainly the ball goes further than a wound balata ball did in previous years.  Also, the club heads are bigger, the swing speeds are much faster, the shafts add more and, while I know that Geoff likes to mock it, the players in general are in a hell of a lot better shape.  Add it all up and I agree that golf today is a different game than 20 or 30 years ago.  Should it be changed?  In my opinion it probably should, but I'm not sure that rolling back the ball is the answer, but I've been back and forth on that a number of times.

I must admit that after reading this report I need to eat a dinner full of crow.  However, I still have questions...

First, I would love someone to check the accuracy of the chart that shows a "selected" grouping of tour pros gain in distance.  I would like to know who the pros are that they are speaking of and see the actual data that shows the distance increase they suggest has occured for these pros.  I seem to recall checking many tour pro averages and noticing sizable gains for longer hitters, relatively.

Second, they should do a test with balatas from 1995, a Titleist Professional circa 1999, and a Pinnacle circa 1995.  If they showed the same near linear gain in distance from their Iron Byron as the modern ball does then I would say that I have been clearly wrong on this subject.  Maybe it is just a general increase in distance gained by all players that has become a detriment to the game.  I know the balata may not show the same linear results but maybe the Pinnacle and Professional balls would.  I would like to know if this linear gain in distance has been consistent in those balls just as it is in the modern ProV1 type ball.

Third, I would like to see a study on how much side spin is imparted on a ball from different club paths and face angles and whether or not there is a difference in the modern ball from the high-end balls that came right before it.  I would venture a guess that the modern ball doesn't curve as much as balls that came before it when hit with different swing paths and face angles at impact.  If this is the case this could contribute to longer distances.  


Speaking from experience I can say that I have gained a tremendous increase in my average driving distance over the last 5-10 years.  I have also experienced a much less amount of curve or deviation in my ball flight over this period of time as well.  

All in all, it looks as if this might be the USGA's way of saying that they are not going to pursue a rollback and that everything is fair and ok.


Jeff F.

[Brent Hutto]

Jeff,

I too found the whole comparison of Tour players 2000-2005 to be unconvincing. That's just not a comparison that admits any particular interpretation about what should or shouldn't be done about the ball.

The comparison that you want to see is the one I've brought up over and over in discussions of this topic. That made-up meme about "exponential gain in distance" or "more than linear increase in distance" with high clubhead speeds has always been bogus and it's a pity that it had gotten so much currency that it had to be debunked with a study.

The single graph that could most inform our understanding of what's going on with Tour players now and how it has arisen over the past ten years would be to plot distance versus clubhead speed for three balls (forget the Pinnacle). Put the curves for 1995 Balata, 1999 Professional and 2005 ProV1x side by side on the same graph. What you would see is that the ProV1x would be a curve like in today's study, the Professional would be below the ProV1x at high clubhead speeds and the balata would curve down like a limp banana.

That's the essence of what's going on. It isn't the fact that all real-world golf balls will suffer from quadritic-law increases in lift and drag at high speeds. It's the fact that a modern Tour ball does not suffer that effect to the same extent as the balls that were being used on Tour in the late 1990's. This was the assumption that caught the USGA with their pants down when Tour players switched wholesale to solid-core balls.

[A.G._Crockett]

Garland,
I don't think anybody disputes that the "changeover" from balata to solid core balls has really benefitted the pros more than the rest of us, simply because they now use balls that meet the ODS, which has been the same for years.  

They have disputed whether that was fair. TEP called it ultimately fair and I disagreee. Eventually he called me nasty names. I wear that as a badge of honor!

As JohnV says, the issue here has been the debate over whether or not ProV's and the like give more than a 10% gain for a 10% increase in swing speed if the swing speed is very high, but only 10% or less if the swing speed is slower.  I had that impression, along with many others, and it now is evident to me that I was wrong.  The fact that 10% of a bigger number is a bigger number is NOT a nonlinear gain, so I stand corrected.

That is one issue here. And is settled as far as I am concerned.
Another issue here is does the pros benefiting from this change hurt golf.
Several subissues
a) Courses become longer
b) golf becomes more expensive
c) time to play becomes longer
d) pro game is all a boring game of smash and wedge
...
Another issue that the USGA paper did a shoddy job of addressing is did the high swing speed pros gain more than the low swing speed pros.
Subissues
Distance
Flight curvature

How it is unfair for a player who is able to swing faster than me to hit it farther than me escapes me.  That's just the way golf is.

To me, the course length/expense/time issue is something ALWAYS blamed on the golf ball on this site.  I think the changes have much, much more to do with marketing a modern golf course in a highly competitive market place with a growing supply of courses.  Since the vast, vast majority of players aren't hitting the ball any farther than they ever did, how could the distance the ball will travel be responsible for longer courses?  It is just too easy an answer.

[Brent Hutto]

Since the vast, vast majority of players aren't hitting the ball any farther than they ever did, how could the distance the ball will travel be responsible for longer courses?  It is just too easy an answer.

I don't think anyone has made a really convincing case for the golf ball causing longer courses etc. But I think the argument can be made that the only thing there's a remote chance of changing to shorten courses back up is the golf ball specification. My own position is that I'd be willing to see a modest rollback purely in reaction to the fact that elite players hit the ball so far now that courses are getting unmanagably long and expensive and difficult to reconcile with the 99%+ of players who still hit it about 210-220 yards in the air with a (Titanium, high-tech) driver.

[Paul_Turner]

The old bible "Search for the Perfect Swing"  stated this i.e. the COR for a given ball was higher for a putt than a drive.

The improvements in driver have been more significant than ball.

[DMoriarty]

John V.,

Very interesting paper and article.  Kudos to the USGA for finally publicly addressing some of this stuff.  We have much to digest and much to comment on, but a little at a time . . . .

First . . . .

Garland, for a number of years, there have been people on this site and elseware arguing that the ball went disproportionately longer when you swung faster.  That is what this test disproves.

I think you are misrepresenting the dissenting opinion.  At least you are with regard to my opinion, and I of course can only speak for myself.   I am not talking about just swinging faster as your summary implies---Few can just decide to  swing faster.   To the contrary, I am talking about different golfers with different swing speeds, and the relative benefits they receive from technology.  

What I have been saying (and I can only speak for myself) is that some of the newer balls (such as the ProV1x) have benefited the fast swingers more than they benefit the slow swingers, thus creating a enlarged distance gap between fast and slow swingers.   As you know from our past discussions, this has absolutely nothing to do with diminishing or increasing slopes, but rather has everything to do with comparing the different distance characteristics (slopes) of two different balls.  

Let me put it this way.  Say we have a fast swing golfer (say 125 mph) and a slow swing golfer (say 80 mph) who both switch to the ProV1x from the ProV1 (or even from some low-priced "distance" ball.)   I don't think that the 80 mph golfer will experience the same distance increase as the 120 mph golfer.  

Now, it may be that this USGA calls into question my premise as well.   I will read it thoroughly and let you know what I think.  But merely demonstrating that the slopes are diminishing says nothing about whether two different golf balls have different slopes and values across a range of distances.