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#### Cross Wind Calculations

Mon, Jun 27 2022 1:18 AM (109 replies)
•  MGB01 1,469 Posts Fri, Feb 26 2021 9:20 AM
Redmonod:

@MGB01...do you adjust the wind velocity based on which course you are on?

i hit less for topspin shots ...and more for backspin shots.....my chart is accurate with ding....and like yiannis said some courses play a little stronger or less with wind ....nothing is set in stone but my chart is a good base to start with...
•  DuFussMcGoo 2,742 Posts Fri, Feb 26 2021 9:37 AM

But really, your system is very interesting to me. Can I have a copy of your blog, or can you give me the location of the information? I'd love to read it. I'm always up for a game improvement.

•  DuFussMcGoo 2,742 Posts Fri, Feb 26 2021 10:27 AM

Nice! Good thoughts.

I feel the same about the terrain.

As for the other differences, they're probably all true, but when I'm playing in a "head to head" competition I have 45 seconds to get the shot off and I'm not that good at figuring the shot out within the time frame given.

Also they stick me in the parking lot for my tee shot!

•  Yiannis1970 2,953 Posts Fri, Feb 26 2021 10:56 AM

Redmonod:

This is interesting...two Tour Champions that don't agree on whether wind speed varies by course. That is, if the wind speed average is 20 mph, the ball will behave the same way (or not) on St. Andrews as Pinehurst. I am just a poor Legend, so don't have much room to argue, but I'll step my foot into it anyway.

I believe two things: WGT displays the wind speed as measured at a given height above the ground. As the ball follows its trajectory (which depends on club, spin, type of ball, how hard the ball was hit, temperature, etc) the wind speed at the ball height will change (being less near the ground and greater the higher it goes). I think that 20mph as measured at St. Andrews is the same as 20mph as measured at Pinehurst. However, the second thing I believe is that WGT takes into account the terrain features of a given hole. So, Pinehurst with its tree lined fairways which block some amount of wind up to the tree height will have a different wind effect than at St. Andrews with it's lack of trees. A rough way to simulate this difference would be to reduce the 20mph wind at Pinehurst to something like 12mph for cross winds, but leaving head and tail winds closer to 20.

Any thoughts?

I wouldn't say that it's unusual 2 TCs disagree on a matter. Everyone plays at his/her way. However, i wrote ''Usually on the Ocean courses you need to play ''more'' wind''....

So, i have to ask. What Pinehurst has to do with Ocean course? Is it an Ocean course?

I will try to explain some of the factors with an example:

Let's say you play St Andrews and you have a distance 183 yards with 15 mph side wind. Let's say you do your calculations and put your aiming point at 10 yds away from the flag, ok?

Now, we go to execute the shot. What type of shot are you going to play? 6 iron 100% fbs, half back, flat? Or 5 iron at 92%? The distance of the clubs in these 2 situations are the same = 180. Do you believe you gonna have the same result if you hit flat 180 100% power or 92% with 195??

Absolutely not!!!

The reason is easy to understand. First of all, the 2 clubs are different, one lighter the other heavier. Secondly, 92% of the 5 iron can be in math 179,2 yds, but does not work this way as you depotentiate your stroke. It's not an analogical type of calculation. But let's say for the shake of the example that it is...

An important (actually the most important thing when you set you aiming point on the approach shot) thing is the trajectory (the curve of the ball after the stroke). In the first case you can have an apex of 115 ft meanwhile on a second example you can have an apex of 90 ft. This is an entirely different shot eventhough math says it's the same distance. The curve of these 2 strokes will be entirely different and you are going to get 2 entirely different results cause you don't ''treat'' the wind with same way.

A ball that stays more up to the air will be affected differently from the wind than another one with lower trajectory. That's why a shot with 3 iron keeps rolling meanwhile a shot with 9 iron stops after a couple of yards.

And to prove you that Ocean wind is different, i will give you a test. Go to St Andrews with face wind (6 oclock)...no matter how much strong it is. Stay at about 130-140 yds and play a flat shot. Then go to PB on the first hole and try to find the same distance and wind condition on the first hole. Repeat exactly the same shot you did at St Andrews and see what happens...

•  MGB01 1,469 Posts Fri, Feb 26 2021 1:45 PM
DuFussMcGoo:

But really, your system is very interesting to me. Can I have a copy of your blog, or can you give me the location of the information? I'd love to read it. I'm always up for a game improvement.

i dont have indepth blog or complicated thoughts....the chart i made was from weeks hitting shots into all the sidewinds... other than side winds then i play by feel...i am clueless with of centre winds at 8 oclock etc....just feel comes into it then....many players have calculations for off set winds ie ...walk of life or young46 are guys with better knowledge....
•  Redmonod 22 Posts Fri, Feb 26 2021 4:10 PM

I use a physics-based model for almost all shots, even putting, which is the exact opposite of how you play. I'm always in awe of players who can play by feel and be so successful.

Your chart gives very similar results to my model for neutral spin. Did you make a chart for full backspin? How do you make that adjustment?

•  Redmonod 22 Posts Sun, Feb 28 2021 9:11 AM

It sounds like your post should be addressed to DuFussMcGoo that apparently uses the same side wind adjustment for every course, not with me. I'm amazed that his approach statistics are so good using that method, but I can't argue with his results. I'm just trying to learn here, not argue with anyone.

I agree with everything you said about trajectory. It's affected by a LOT of factors. In your example PB has about the same height above sea level as SA, and sometimes the same temperature. The factors that affect trajectory (temp., altitude, humidity) means that the same shot hit the same way when the temp and humidity are the same should have about the same result at either course, IN THE ABSENCE OF WIND. Wind adds a whole different element and that was what I was asking about in my first post. Is a 20 mph wind at SA different than a 20mph wind at PB  because of the lack of trees at SA, or does WGT assign a different value to the 20mph at each course?

•  DuFussMcGoo 2,742 Posts Sun, Feb 28 2021 10:18 AM

Thank you Yiannis1970 for a nice explanation of your thoughts. Terrific ideas.

My dinging (which is at the center of everything) has dropped from 70% to about 20%. A year ago I used IE and played on my computer with a Windows 7. Now I'm using the outdated Windows 7 and WGT Launcher. I think when I get a new computer with Windows 10, I'll play somewhat better, but not for a while.

Again thank you and stay safe.

•  Yiannis1970 2,953 Posts Sun, Feb 28 2021 2:08 PM

You are very welcome, stay safe too!!

PS

Stay with 7 forever...trust me!!! :)

•  MGB01 1,469 Posts Wed, Mar 3 2021 11:43 PM
Redmonod:
Did you make a chart for full backspin? How do you make that adjustment?
sorry no i didnt....but i think full backspin would add maybe 5 yds more movement to a shot on my chart....my chart was made with nuetral spin....