Who cares what is driving the size wars? F3J is a very miniscule part of the soaring scene is the US. Most of the people buy the Perfects, High Ends and the new Icons are buying them to compete in TD contests and not F3J. So the problem exists when they show up at a contest and the lines start breaking.

It is more than the "fly it out" mentality, it is contest management. When the line(s) break they need to be fixed. That is down time. It is not fair to the contestants and the contest staff.

Darwin N. Barrie
Chandler AZ
On Dec 20, 2007, at 10:38 AM, David Klein wrote:

You guys really aren't looking at the international trends that are driving the size wars. These planes are designed as the ultimate F3J plane. In F3J, the launch power is as much as you can use, figuring you higher some offensive lineman to tow. If F3J were to switch to using F3b winches, the launch power is regulated. F3b has evolved to smaller planes, that launch higher in a no wind, or downwind launch situation. If F3J planes were to go to a regulated launching system, the planes would get smaller, in order to launch higher faster in weak launch conditions.

So the planes will continue to grow as long as there are large towers with a lot of power to launch them. Bigger planes are more efficient, so If you can launch them, you are at an advantage. Planes will grow unless we regulate launching power.

BTW
We don't have a winch power problem we have a winch line problem. We use crappy/heavy braided line rather than high performance Mono filament spectra. The mono is temperamental, so I don't recommend switching out club winch lines, but just understand the problem.

If F3J switches to F3b style regulated winches, the planes will come back down in size, or at least stop growing.

On Dec 20, 2007 9:32 AM, tony estep < [EMAIL PROTECTED]> wrote:
----- Original Message ----
From: Darwin N. Barrie < [EMAIL PROTECTED]>
...My concern is the launching equipment. With the current crop of moldies, line breaks and winch bogging and ultimate failure are becoming more prevelant....
======================
I wonder about this too. The Pike Perfect is the current WC plane and the current Nats champ, at a bit over 140", and has apparently set a new benchmark that eclipses the 132" planes, which in turn pushed out the 3-meter (118") planes. It's all too easy to break the line with a PP, and line breaks will presumably be even more likely with 150" planes that have larger wing areas and can generate more pull.

The 2-man tow setup puts a practical limit on F3J, but apparently that limit is not fully compatible with the standard U.S. winch setup; that is, it seems that the F3J scheme can launch bigger planes than our typical winches like to handle. One imagines a nightmare scenario where the planes keep getting bigger, and eventually as clubs need to replace their launch gear, they'll turn to super-power Injoy or similar winches, and the cycle will repeat, and finally we'll be flying models 40% of full-scale like the gas- power boys.



--
David Klein
Graduate Research Student
Department of Structural Engineering
Jacobs School of Engineering
University of California San Diego


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