RE: ShopTalk: long drive

[Lloyd Hackman]

PatK

 

At the point of impact, acceleration has nothing to do with ball speed. The momentum transfer equation is 1/2 M V^2. Acceleration creates velocity but only the velocity at the time of impact maters. Since mass enters into this equation the 5g will add 5 yards to the distance (at 100% efficiency) if you got 200 yards prior to adding the 5g, or 2.5% more force.

 

llhack

 

 

----- Original Message -----

From: The Kelley's

To: [EMAIL PROTECTED]

Sent: 10/12/04 9:09:15 PM

Subject: RE: ShopTalk: long drive

David,

You need to have acceleration information for each combination to evaluate the data - I'd expect that the longer shaft is allowing the player to accelerate the clubhead a bit more as impact approaches than the other drivers, thereby imparting a bit more force to the ball.  I'll offer that the 5g difference in clubheads in your test is not significant with respect to the force imparted on the ball, as seen in the #2 and #4 test data.

 

Good Luck,

Pat K   

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]On Behalf Of [EMAIL PROTECTED]
Sent: Tuesday, October 12, 2004 1:41 AM
To: [EMAIL PROTECTED]
Subject: ShopTalk: long drive

Hi All,
Im working with a long drive competitor and he is getting more ball speed with less club head speed with a 50" driver with a 200 gr head than he is out of 2 other 48" drivers with 195 gr heads and another 48" driver with a 200 gr head.
Im trying to understand if this is due to the extra mass of the head and or club over all or if it somehow has something to do with the length such as the head lagging on the longer shaft.
The smash factor increased substantially with the longer shaft and heavier head even tho! ugh the club head speed went down to the extent that Im wondering several things including where the point of diminishing return is.
All these heads border on the line of cor and can't really exceed it by much or they will fail due to the collision.
Here's what I know from the fitting session on the launch monitor at the Titleist facilities.

driver            1          2          3          4
avg chs       142       148      148       150
avg bs         206       198      198       202
club length   50"   ! ;     48"     &nb! sp; 48"& nbsp;      48"
spin rate    2100       2100     2200    2400
hd wt         200gr      195gr    195gr   200gr
launch a     11.5        12        12.5     12.5
hd vol         455cc     444cc   450cc   400cc
my smash # 1.45      1.33      1.33      1.34
The shafts were all the same model and very similar in spec's and all spined and flo'd with s1 at 12 o'clock.
The session went well as far as ball striking goes in the competitors mind in spite of the smash factor #'s, maybe at that clubhead speed smash fac! tor goes down.
He says that they had about a 30 foot long rolling tent set up at 330 yards from the tee and he hit 16 balls in a row over the tent using it as the center of the grid,
that's a good amount of carry on a pretty straight ball.
Any ideas on what can be concluded from this data?
David