February 19th, 2011 
admin I am writing a paper on how fly fishing is related to physics and need some averages in order to do calculations.
Average length of rod. I came up with 8.5 feet. Does this seem accurate?
Average mass of rod? Measured in grams, kilograms, or pounds.
Average mass of line and fly?
Average time it takes to move wrist 45 degrees during cast?
Average time line is in the air – measured from after wrist movement is done until the fly hits the water?
Thanks!!
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I’ve used a fly rod some and will attempt to answer as accurately as I can based on my own knowledge.
8.5 feet would probably be correct, I have two, one 9 ft. and one 7.5 ft.
Rod Weight would be close to two pounds w/o reel attached.
Mass of line would be about 18 oz. weight.
Move wrist 45 would be 2 sec.
Line in the air would be 8 sec. because the tippet that the fly is tied to is lighter and last to hit.
Average length of rod. 8 1/2 feet seems fair
Average mass of rod? approx. 3 1/2 oz
average wt. of reel would be approx. 4 .5 oz
Average mass of line and fly? let’s say it’s a 5 wt line (very popular)
wt is approx. .32 oz, add 9ft leader + size 14 dry fly and we’ll say
.34 oz.
Average time it takes to move wrist 45 degrees during cast?
I’d say 1 second
Average time line is in the air – measured from after wrist movement is done until the fly hits the water? for a 30 foot cast with a med/fast action rod, between 3 and 4 seconds
Yikes!!
1. How do you determine “average” length? Modern production fly rods have lengths varying between 6.5′ and 16′. This doesn’t even consider custom/antique rods. Rods of 8.5 are *common* but are not average.
2. Same problems as #1…plus it’s compounded further by the use of different materials and rod design (tapers, wall thickness, etc)
3. Which line? They come in different tapers, and you’d need calipers and a grain scale to be accurate.
4. The cast is not made with the wrist.
5. Do you understand that casting is composed of both a backcast and a forward cast? The line leaves the water’s surface, and thus becomes airborne, early in the backcast. The duration the line remains in the air depends on the length of the cast, the action of the rod, the casting style of the angler, the weight/taper of the line, wind conditions and other factors I don’t even think about.
I’m not trying to mock you, but from a scientific standpoint, don’t you think you have too many variables?