PFK & elastic

An elastic bridle on the PFK is no easy matter as it has a keel; so I thought I’d try something simple to start with: adding elastic as a damper to the flying line to see if the movement imparted into the rig could be sufficiently damped to just let the angry red delta do its thing and let me shoot sharp pics. I put one at the kite:

and one just before rig attachment like this:

The line is larks- headed around the ends of a bungee luggage strap.  I left a decent loop of line slack to accept the stretch of the bungee. I didn’t take too many shots with the rig aloft as I had to cut the flight short on being beset by curious cows, but those I got, while mighty dull, are reasonably sharp:

The kite was still veering about wildly in the turbulent airflow but the rig seems to have been spared a lot of the vibration that has ruined exposures before. Another bonus of the elastic dampers is the kite is a bit easier to hold. Aiming the camera is still difficult as there is still a great deal of the kites ‘tracking’ movement in the viewfinder: this kite is still not as stable as I’d like in big winds, but with damping on the line, I at least managed to get something in 20 -22mph!

So, the next thing to try with this kite is a drogue, to see if the tracking can be smoothed or slowed and then perhaps I can begin to feel happy with it as a sky hook.

About billboyheritagesurvey

Heritage worker
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6 Responses to PFK & elastic

  1. Arni Geirsson says:

    Interesting! I often use the Nighthawk, usually in 10-15 m/s (22-33 mph) and find it very stable. In my experience, the high wind per se does not cause more camera movement but it extends the area where lee side turbulence and ripples caused by features on the ground could cause excessive movement. My instinct would then be to put the kite up higher, into smoother wind. When I am flying the kite, I find that keeping the line tension constant reduces camera movement considerably because less tension causes the weight of the camera to sag, only to shoot up again when normal tension returns – I am sure you have the same experience. Therefore, I have often thought about some means of keeping the line tension constant, like a constant torque winch or a weight of some sort that pulls the ground end, with freedom to move up and down with constant downward pull. But maybe it is best to do this by hand and enjoy the “conversation” with the kite, through the line. I look forward to hearing how useful the elastic is but it seems to me that it would not keep the line tension constant nor act as a damper, meaning that it would dissipate energy (it should just store it).
    Greetings from windy Iceland – Arni

    • I agree that getting the Nighthawk up into cleaner air would help but I have 2 problems.

      1 I am limited to 60m by CAA regs
      2 As wind speeds build in gust (30mph +) I find the Nighthawk tends to veer down and to one side of the wind window (usually the right) .The more line I have out the harder it is to manage this when the gust lets go…the kite piles on the speed as it soars back to the apex of the window.

      I have thought about getting the kite to tow a drouge to slow the big swings down but decided against it as the change in the kites attitude from gust to lull is huge and I though I might kill lift when I needed it most!

      It is this jerking about that led me to the elastic idea. To be honest I’m not happy with the stability of this kite, it just seems to be a loud angry thing in the sky BUT it takes the big wind like nothing else I have.

      From looking at your shots of beautiful Iceland it looks like you are spared the trees, houses and overhead cables I have to deal with here!

      Thanks for the comment!

  2. Arni Geirsson says:

    Sometimes, my Levitation delta tends to veer to one side and I have not understood what the cause is, but it must have something to do with the symmetry of the kite (or lack thereof), requiring some subtle adjustment. My Nighthawk has not shown this tendency. And, yes, there is not much here to disturb the wind… 🙂

    • I first noticed this trend with the HQ2.0 (Becotised, thank you Christian) which I discovered was really good in 15-22mph winds. In gusts it would start to veer and drop, but still pull like a horse! What’s happening is that its being blown out of the way of the wind! All kites have their limit and this is expressed as a tendency to be blown either to the left or right as they reach the upper limit of what they can cope with. It is a matter of judgement whether the kite should come down or be left to recover when the gust passes. I was surprised the Nighthawk developed this characteristic in the high twenties as it says on the bag it’s good for 40Knts. It has 3 tow points and perhaps I have to learn which one to use for a given wind speed 😉

  3. Barry Carpenter says:

    Sounds very much like the PFK reqiures tuning a little.

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