These two kites were an experiment in using 3 bamboo skewers end to end instead of just 2. Both designs flew very well and were exceptional in very light to light winds.
These 3-Skewer kite posts once appeared in the site blog page - that's the one you enter via the 'what's new!' site navigation link. Just scroll down and stop at any heading that appeals :-)
3-Skewer A-Frame Kite
The 3-Skewer A-Frame
The 3-Skewer A-Frame
3-Skewer A-Frame Torture Test
Although the winds were gusting to quite fresh strengths, I decided to pull out the A-frame kite anyway, to do a final check of its behavior when pushed to the limit.
A short flight on just 10 meters (35 feet) or so of line confirmed that a much more forward towing point might be a good idea! After shifting the Prusik knot towards the nose by a good couple of cm (1"), the upper bridle loop had a distinctly swept-forward look when all the lines were tight.
For the lightest conditions, the 2 upper legs of the bridle come away from the kite at roughly right-angles, when viewed from the side.
Well, the kite went up and still got driven back down to low line angles during the strongest gusts. However, it seemed noticeably more stable with the forward towing point. The wind twirled the tail into a tight tube for most of its length, making it less effective. Yet the kite pointed straight up most of the time. Including during some extreme air pressure treatment!
The A-Frame kite suffered but did not break, side panels fluttering loudly in the breeze. All 3 spars bending noticeably.
I let out around 50 meters of line for a while, and watched the kite soar up high in lulls and get driven down - tail first - during gusts. The reverse of what usually happens with kites! Looking at the wind meter after packing up, the breeze had peaked at 23kph near the ground, with an average speed of 8.8kph. But there will be no more torture tests for this 3-Skewer A-Frame kite. It's a dream to fly in light winds and thermals.
3-Skewer A-Frame Soars In The Sun
A rare sunny day with moderate winds provided another opportunity to get out with the 3-Skewer A-Frame again. I was hoping for some fresher-strength breeze to really push the kite hard and give an opportunity to trim it properly.
Firstly, I let the kite out at about 30 degrees of line angle. Just for fun, I let the line out just fast enough to hold the kite at around 30 degrees all the way out to 60 meters (200 feet) of line. Then, I stopped and the A-Frame rose to around 45 degrees.
The stronger gusts kept bending the kite and pushing it down to lower line angles, so I brought it back down by anchoring the line and walking out with the line slipping through one hand. The towing point was easily shifted forward by a centimeter or so (1/2") by sliding the Prusik knot and then locking it again in the new position.
This time, the kite was much more comfortable and rose right up to 60 or 70 degrees. Even after letting out another 60 meters of line!
For 15 minutes or so I just enjoyed seeing the 3-Skewer A-Frame flying steadily at high altitude, the loop tail rippling just slightly in the breeze. Orange plastic brightly illuminated by the late afternoon sun from behind. No sign of leaning, strangely, despite the good moderate airflow at that height. Perhaps unwinding the tail to its original state had made quite a difference. Can't complain!
On the ground, the wind meter recorded an average strength of 5 kph and a maximum gust of 14 kph. Towards the end of the flight, the fresh gusts had died down quite a bit. As a result, the kite hung lower from time to time during lulls.
3-Skewer A-Frame Over The Street
Got a bit daring just before sun-down last night. Let the 3-Skewer A-Frame right out to 60 meters (200 feet) from our side lawn. There it was, hanging over the street in the dusk, floating about in the cool light breeze. No power lines anywhere close, I should add.
Well, wouldn't you know it, the breeze freshened a bit more, and the kite started the dreaded lean-to-the-right... (yet more trimming tape required on that wing-tip, evidently)
After a few tense minutes of winding in at every hint of a lull, the kite finally came safely over our property, then our roof, then into my hand. Phew! All's well that ends well.
Slope-Soaring The Roof At Sunset
Yes, it's another one of those back-yard kite flying reports! Just on impulse, less than half an hour before sunset, I went out to the side lawn with the 3-Skewer A-Frame kite hooked up to our 20-pound line. A light breeze was rustling the tops of the bushes and small trees. Just occasionally, a small puff would find its way through the yard lower down, despite the solid fences and walls on all sides.
A few tries were required but eventually the A-Frame kite popped up above gutter level and caught enough breeze to continue up.
What followed was a flight which required constant attention, but was pleasant enough anyway. Fun, even! The main obstacle was the TV antenna, which could be avoided by moving the tether-point (me) side to side across the lawn. Also, when it was clear that the wind strength was not going to over-power the kite, I let some more line out so the kite was just a lot higher than the antenna.
The wind was gusty as usual, so the kite often found itself floating just over the tiles during lulls. This was a little tricky, since the air was generally slower down there anyway. A hasty pull-in to climb back to faster air was often required. The exception was when I was able to position the kite right in the slope-lift region of the roof. The direction of the roof's ridge-line wasn't ideal, but it seemed enough to give the kite a bit of a boost.
As the sun sank further, the wind died down and it became impossible to keep the bright orange A-Frame up there. Soon, it had to be pulled all the way in to a hand-catch over the lawn. Carrying it back to the shed, I noticed the sky turning to the intense pinks and reds of an Adelaide summer sunset.
Perfect Weather Ruins Experiment
Let me clarify a bit... It seemed the breeze outside might have been gusting just enough to push the 3-Skewer A-Frame kite close to its limits. This was good since I wanted to try something.
The A-Frame has a rather short upper bridle loop so I had initially ignored the possibility of trimming the kite straight with the upper sliding knot. But today I thought - why not at least give it a try. If the amount of adjustment available proves to be enough, there would be no need for that ugly tail-let out on the tip!
To cut a full flying session short, the wind speed proved to be just perfect for the kite today. The darned thing flew straight as a die even without the tail-let in place! A perfectly pleasant flight on 60 meters (200 feet) of 20 pound Dacron. The A-Frame kite did loop a few times, but that had more to do with the loop tail being a bit rolled-up and ineffective than with any lack of trim. In other words, it looped in both directions, at random.
Aren had a bit of fun with the original 2-Skewer Diamond, which has been bequeathed to him now.
Just before returning home, the wind meter was held shoulder-high for a couple of minutes... 5.8kph average and gusting to 12.5kph. A nice kite flying breeze for light-wind designs!
3-Skewer A-Frame Great In Light Winds
This kite is one of three bonus kite designs planned for the Making Skewer Kites book. As such, the instructions won't be available on the website. As a natural progression up from the 2-skewer designs, these 3 kites use 3 bamboo skewers end-to-end as the basic building unit. That's just over twice the sail area of similar 2-Skewer kites.
I actually had a couple of sessions with the A-Frame today. The first was on only 30 or 40 meters (100 feet+) of line, in very light air. Despite only making a 45 degree line angle, this flight enabled me to get some good photos and video. The kite flies smoothly on its 4-point bridle, as you would expect, starting to rock slightly when there is hardly enough air pressure to keep it up.
The horizontal spar flexes noticeably if you tug the line, giving the kite a spongy feel not unlike a Delta - but without Delta vertical acceleration...
The next session saw the kite rise easily to just under 400 feet, again in very light air. It looked quite photogenic up there, the bright orange panels illuminated or in shadow from the late afternoon sun. Black plastic looped tail hanging down almost motionless.
20 pound line is just perfect for this light-weight A-Frame kite. On this flight, it had a bit of thermal help up to high line angles. At no time was there much tension in the line. It's just a great light-wind kite!
3-Skewer Sled Kite
3-Skewer Sled Trims Nicely
In an earlier outing, moving the bridle knot didn't seem to do much. So today, with breezier conditions, I tried an experiment with a little air-bucket taped to the trailing edge, on 1 side.
With the kite in the air, it still seemed to loop right in stronger gusts so there was no option... Shift the knot a lot further and see what happens! This was quite fortunate since the knot shifting worked very well. However it was somewhat counter-intuitive since to correct a loop to the right I had to shift the knot in the same direction. For most flat kites it's the opposite.
After toying with the knot position and seeing the 3-Skewer Sled veer off obediently in either direction, I used 2 or 3 short flights to get the knot position close to perfect. The air bucket wasn't needed so I got rid of it. Then, up the Sled went in moderate strength wind. Right up to some pretty steep flying angles I'm happy to report! The breeze was cool and gusty but there was no trouble with collapses.
Checking the wind meter at shoulder height for half a minute, it registered an average of 11kph, gusting to 21kph. It must have been gusting into the high 20s up at 150 feet but the 3-Skewer Sled was quite comfortable. Then I started letting more line out...
Unfortunately there was trouble after that, when one of the top corner spar caps ripped out. Never mind, some extra reinforcement with packing tape will fix that. The mod should allow the kite to fly reliably over the whole Moderate wind range - from 18kph right up into the high 20s. The towing points were showing no signs of strain at all.
3-Skewer Sled Collapse-Proof And Efficient
With a gusty light breeze and sun peeking through outside, it seemed an ideal time to test the new 3-Skewer Sled. 3mm skewers were unavailable in the shops, but the 4mm ones are probably quite ideal for this 3-Skewer design and others which will follow.
The kite has 9 skewers in total, plus some short reinforcement pieces. However each spar is approximately 3 skewer-lengths long, hence the 3-Skewer designation.
A photo was taken with the kite on only a few meters of line, brightly lit by the sun. Letting out line to over 30 meters (100 feet) was easy, although lulls sent the Sled back towards the grass from time to time. More photos this time, and a few videos. So far, so good!
Due to the ample width of the skewers, hence a bit more weight, this kite didn't soar on the very lightest puffs of wind. Who cares, most of my 2-Skewer kites are good for that, with their 3mm or even 2.5mm width skewers!
The 3-Skewer tail-less Sled kite waggles slowly left / right under low air pressure, but settles down to steady flight as the wind speed comes up further. This kite seems to sit at around 50 or perhaps 55 degrees from the horizontal when wind strength is ideal.
Soon I had the line out to just over 100 meters (300 feet) and the 3-Skewer Sled proved very reliable compared to most 2-stickers I have flown. Not one collapse, and not even much billowing in and out despite some roughness in the air. It does seem to pull a little to the right, but a small bridle adjustment should fix that.
Despite the cold late afternoon setting, the bright orange Sled briefly floated right up to 70 degrees or more in a patch of rising air. Nice!
This kite is a perfect match for 20 pound Dacron line, pulling it almost straight much of the time, yet without a risky amount of tension.
Measured near the ground, the wind meter showed an average of 3.4 kph and a maximum gust of 12 kph. A thought crossed my mind - why bother with 2-stick Sleds at all... The 3 spar Allison Sled with its sloped side-spars was really an inspired concept!
Two Skewer Sleds Tested To The Limit
It was blowing quite a bit outside, but I thought it might be instructive to take out both the 2-Skewer and 3-Skewer Sleds and see how they handled it.
Down at a nearby school oval, the 2-Skewer Sled went up first. Some days ago I had removed some area along the center-line of the kite, bringing the spars slightly closer together. To cut a longer story short, the kite behaved similarly as before. However, this time it seemed almost immune to leading edge collapses through sheer speed, when gusts would force it to fly very fast in the direction it happened to be pointing. That was good!
Unfortunately, it still had a strong tendency to collapse when it reached high line angles while under high line tension. Perhaps that's not too much of a problem since it is supposed to be a fairly light-wind kite after all. It just needs to be flown in more suitable conditions.
So, out with the 3-Skewer Sled. Within seconds of getting it to around 50 feet, an almighty gust caused one side spar to bow alarmingly out to one side. The spar caps at each end managed to hold. I've never seen that before, but it was a clear indication that taping the middle of each Sled spar to the sail is a very good idea! That's been done now, and I'll be updating all the relevant instructions.
Near ground level, and in a somewhat sheltered position, the wind meter had recorded an average of 6.6 kph with gusts to 22 kph. Closer to 30 kph at around 200 feet perhaps. With such hairy flying going on, there hadn't been an opportunity to let out much more line than that! Must be nice to these Sleds from now on...