Diamond Kite Nose Diving
Hi. We are building a kite for my daughter's science class. The only problem with the diamond kite is that once it goes up a few feet, it turns over and dives straight in to the ground... Why?
Is it the focal point being in the wrong place? We have strings from the 4 corners meeting at a focal point, to which the main line is then attached.
Please help! Thanks.
Firstly, I don't know whether your kite design is a proven one, supplied to the students by the school. So, I'll first try to fix what you have. As an alternative, I will also suggest one of my easy Skewer kites - which is guaranteed to fly well if made according to the instructions.
Your 4-string Diamond Kite
OK, so you have put together a Diamond kite with a bridle line from each corner. Unusual, but there is no reason it won't work if adjusted properly. For most Diamonds, the towing point (what I call your 'focal point' :-) should be around 25% of the distance down the vertical spar, from the nose of the kite. (The vertical spar is the stick going straight up and down.)
In other words, with the kite lying on its back and all bridle lines straight, they should all come together directly over the vertical spar, and, looking from directly above the knot, 1/4 of a spar-length from the kite's nose.
My initial thought was that your 'focal point' is too far towards the nose. Shift it back a little towards the tail if necessary. But no further than 1/4 spar length from the nose.
My second thought was that your kite might be a little heavy. Believe it or not, this can really affect the kite's stability. The easiest place to save weight is in the spars. Just use thinner materials. Avoid excessive use of tape or paint or other decoration. The type of sail plastic you use will generally not make much difference - all thin plastic sheet is very light.
Add a nice long tail of course! At least 8 times the length of the kite itself should do it. A simple single-streamer type of tail is fine. But again, keep it light.
So, you can try again with a lighter kite, and experiment with shifting the towing point just a small amount at a time until it seems to fly better.
Fly the kite in wind that is not too much stronger than that required to just make it climb.
If there is almost no wind, then try walking or jogging into the wind to fly the kite up. Running is almost never necessary with a well-built kite!
If you prefer, or if you finally give up on the 4-string version...
The MBK Tiny Tots Diamond
I'm sure your daughter is not a 'tiny tot'. However, this kite might be worth a try because it is truly very simple and almost foolproof. It doesn't even have a bridle as such, since the flying line is simply attached to where the sticks cross! Surprisingly, it can put up with quite a bit of wind too, with sufficient tail attached.
Here's how to make the Tiny Tots Diamond.
Thin bamboo BBQ skewers make wonderful kite spar material since they are so light and yet strong. I've made dozens of kites with them, sometimes using 2 skewers for each spar.
Anyway, I hope that science project comes to a successful conclusion soon!