[aprssig] Field Day balloon repeater - question

[Richard Amirault]

----- Original Message ----- 
From: "KY1K"
Subject: Re: [aprssig] Field Day balloon repeater - question
(snip)

> Kites are more practical, though not for the weak at heart. The problem 
> here is that even a moderate change in wind direction (10 or 15 degrees) 
> makes a big drop in the lift until the kite realigns with the new wind 
> direction.  Short term (sudden) wind changes are inescapable.

Baloney! There are plenty of times where the wind is unchanging ... it all 
depends on where and when you fly.

(snip)
> IF (and that's a BIF IF) you can get a 30 to 50 square foot area kite off 
> the ground, it can lift 4 ounces per square foot of load in low wind 
> situations.

Define "low wind"  .. it would seem a good definition of "low wind" is "just 
enough wind to get the kite to fly" .. under those circumstances the kite 
will not be able to lift any load off the ground.

Also, not all "30 to 50 sq ft" kites are the same. Different kite designs 
react (fly) differently. Each has it's own 'wind range' that it will fly 
well. A 50 sq ft parafoil will not fly the same as a 50 sq ft sled or a 50 
sq ft genki.

> To do it, and to keep it up, you need a means of controlling the lift, 
> which is usually done by remote control by changing the attack angle of 
> the lifting surface. It can be done, and you can keep them in the air for 
> days....but they will tend to come down as weather fronts pass and the 
> wind direction changes abruptly, wind that changes direction every 30 
> seconds will bring anything down.


More baloney. Changing the angle of attack will do nothing if the wind dies 
.. or falls below the "wind range" for the particular type of kite being 
flown.

Richard Amirault                                N1JDU                Boston, 
MA, USA
www.erols.com/ramirault          "Go Fly A Kite"