Rate of line fall / DRAG / Definitions

Gordy - the fall rate is dictated by gravity and terminal velocity. Neither the loop nor the line have

any special abilities to negate these from what I can see. Tension in the line gives the illusion of

increased hang time but it is an illusion.

Talking about drag here:

Someone pointed out this excellent paper on throwing the javelin:

http://www.athleticscoaching.ca/UserFiles/File/Sport%20Science/Biomechanics/Throwing%20Events/Javelin/Ogiolda%20Javelin%20and%20the%20Role%20of%20Speed.pdf

While javelin throwing isn't exactly the same as casting a fly line there are many

similarities - especially when we look at the motions of casters like Hartman

and Arden.

A javelin throw starts with as much drag as possible until the arm is in the most powerful

position to begin rotation about the elbow, wrist, fingers.

When we look at the speed curves of various body parts throughout the throw we see

that body parts that are in motion tend to stay in motion (shamefully stealing from

Newton on that one) throughout the throw. They reach individual peak speeds at different

points in the throw but they do not come to a complete stop, they decelerate. In that sense

the translational movements (drag) continue through to the end of the throw. If we chart

the path of the javelin thrower's hand it will move in an ellipse - not a perfect circle. So

in that sense as well the translation did not come to an abrupt halt just because

rotation began.

I believe the same is true for casting. Translation does not come to a full stop when

rotation begins. I think the confusion is that we have different words for translational

elements of the cast but not for the rotational elements. So, by defining drag as

the translation leading up to rotation we can certainly say that drag ends when rotation

begins because we have defined it that way. That doesn't mean that translation came

to an abrupt halt - it just means that the drag phase ended.

I prefer the view you stated:

"My way of looking at it is that translation can be pure linear motion or any linear motion of the fly rod whether or not combined with rotation."

Gordy - on the skin drag/form drag thing - the Gatti-Bono/Perkins paper estimated the lift

for a climbing loop shape to be about 4 times that of a symmetric loop shape and this was

due to form drag.

There is a saying in mathematics - 4 times a very small number is a very

small number. Even if lift due to form drag is measurable I don't think it's going to be significant.

Chase is to be commended for his work. He's addressed a complicated issue with simple and

inexpensive experimentation.

Cheers!

Walter

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Walter... I thoroughly agree on commending Chase for his study ! We need more instructors who are good at taking the complicated stuff and making it simple.

Looking at "small numbers" and considering means and extremes...... 4 times Zero is ZER0 ..

With all this in mind, let's invoke the KISS PRINCIPLE:

LIFT OF THE FLY LINE DUE TO LOOP SHAPE IS NOT IMPORTANT TO THE CASTER.

Gordy

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

From Jim Penrod:

Hi Gordy,
I noted in Paul Arden's sexy loops, I think that it was June 1 or 2 but is available under comments by Paul on Definitions, that he gives his definitions of drag and slide. I thought that they were quite good and made sense. Take a look and see what you think.
Spent five days in N.C. last week fishing the Nantahala and the Tuckasegee and camping. Caught a lot of fish and had a great time. Wow, I even got some nymphing (which for a saltwater fisherman is exciting) although I enjoy the rise and take with dries.
Jim

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Paul's definitions show good thought process. Basically, I agree with his on DRAG.

As I stated, yesterday, I look at SLIDE as a sliding movement of the fly line through the guides prior to loop formation.

Problem with definitions is the concept of acceptance and agreement. As things stand at present, it seems that one man's definition is as good as another's until we achieve general agreement or, better yet, consensus. Until we have that, "definitions" are opinions.

Dictionaries including Websters as well as the O.E.D. often have numerous definitions for a single word. They base them on the most frequent use in past literature and conversation.

Webster's on DEFINITION: 1. The act of defining or making definite, distinct, or clear.

2. The formal statement of the meaning or significance of a word, phrase, etc.

One can use various words to make things distinct or clear. The use of the word, "formal" implies agreement. Agreement or consensus may be that of few or many. The more who agree, the more likely any definition is to achieve common usage.

During my tenure as chair of the CBOG Glossary Committee I read Simon Winchester's book, THE PROFESSOR AND THE MADMAN: A tail of murder, insanity and the making of the Oxford English Dictionary. Bruce Richards is chair of our committee at present and I remain a very active member. After reading this book, I recommended to Bruce that each committee member read it. He agreed.

Lots to be learned !

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~