SLP-Line organized / Humidity / Quiz

"Ally.... I wasn't talking about the orientation, length/shape of the line prior to the forward cast; rather during it. Here, if we have non-smooth application of power (erratic power) we will likely have a tailing loop..... G."

The point that I was trying to make was the importance of the line being in the right place “organised” at the commencement of the cast and the influence that it has on the cast even if the forward motion and “stop” are perfect. Imagine a line dead straight at a high angle upwards behind and you can get a tailing loop and a low angle downwards will produce a wider loop assuming that the SLP of the rod tip is horizontal. Of course if the line behind in not straight – anything can happen! Line arc is important too.

Best wishes,

Ally Gowans

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Ally....

Thanks .... NOW I understand what you meant ! I agree.

The concept of ORGANIZING THE FLY LINE at or just before making a cast is not only valid... but necessary for efficient casting. You introduced me to it. It includes many factors such as line position, distance and angle, slack or no, depth if in water, and the idea that one must have the ingredients to get the end of the line moving before making the cast.

Gordy

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CASTING WHEN THE HUMIDITY IS HIGH

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I had written to Al Crise a statement that I had noted greater difficulty in achieving distance even by some competition distance casters when our humidity here in the Florida Keys was literally at or near 100%. Tom White had noted the same thing.

My opinion has been that this is because the air was denser. In view of Jerry Puckett's informed response, it appears that I was wrong about that. (As most of you know, Jerry has had many years of flying as a commercial airline captain.)

Now, I guess I'll have to try to figure a different reason for this phenomenon. As you may realize, those days with super high tropical humidity are also hot and we are at sea level. Jerry's response is below

Gordy :

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Gordy and Al:

From the "The Pilot's Handbook of Aeronautical Knowledge:"

Page 2-2 Principles of Flight

Effect of Humidity on Density

"The preceding paragraphs have assumed that the air was perfectly dry. In reality, it is never completely dry. The small amount of water vapor suspended in the atmosphere may be almost negligible under certain conditions, but in other conditions humidity may become an important factor in the performance of an airplane. Water vapor is lighter than

air; consequently, moist air is lighter than dry air. It is lightest or least dense when, in a given set of conditions, it contains the maximum amount of water vapor. The higher the temperature, the greater amount of water vapor the air can hold. When comparing two separate air masses, the first warm and moist (both qualities tending to lighten the air) and the second cold and dry (both qualities making it heavy), the first must necessarily be less dense than the second. Pressure, temperature, and humidity have a great influence on airplane performance, because of their effect upon density."

Roughly speaking air pressure at 18,000 feet is half at sea level. So my thoughts on not being able to cast as far when at sea level may be due to the thicker air (humid or dry) due to the pressure of gravity thickening the air mass.

"The Best of the West" casting competition is around 4,500 feet so casting at sea level would be, I think, less distance for the same cast.

Anyway, not appearing to be a Smart *%# but humid air is less dense than dry air given the same altitude and temperature.

I loved flying on the east coast when a dry high pressure system dominated (anything above 30.00 setting on the altimeter.) Thicker air, short ground roll, off and flying!

Hope this helps! So what are your thoughts?

Captain Puckett--Retarded. opps, Retired!

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Jerry.... I do appreciate your information. This was doubtless studied by experts.

Now I'm guessing. Fact IS that I can't reach my max distances when casting here in the tropics at sea level on days when the humidity is high. This might be due to an effect upon the fly line (???) and not have anything to do with the air density. Someday I'll have the answer !

What about atmospheric density of fog ? Here we have fine droplet precipitation which might behave differently than humidity where the woter particles are molecular.

We have fog so rarely, here, that I have not tested my distance capability under that circumstance. (One or two days a year.)

Gordy

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QUIZ RESULTS WITH OUR NEXT MESSAGE !

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