Foil kites on shorter lines

[DukeSilver]

Apologies if this has already been asked before. I'm about to get my Ozone Hyperlink tomorrow and this will be my first foil kite. I noticed that a number of riders, like Frank Rosin, are using short lines with foil kites. Could someone please explain the benefits of shorter lines? I'm assuming it allows better high wind control? If so, what are the physics behind this? Is it worth getting a second bar with 12m or 15m lines when you own a foil kite?

[Regis-de-giens]

Short line gives you better speed and upwind angle. Reason is that drag of the lines is reduced. But it is more sensitive on a high LD ratio kite like race kites.
You will also benefit from higher end , specially in gusty winds. Reason is that the kite needs less travel (So less time) to reach its "new" extreme side of wind window. Air tack is a bit easier for same reason.

BUT ...
You will loose ability to loop the kite without damaging its glide. Less time to loop and less power full loop. Hence less overall power for waterstart. So low end is degraded.
To work your loop during a air jibe, it will give you less area so timimg shall be better and risk to put the kite in water is higher.

For a medium ratio kite like Hyperlink, Pulsion, Soul , etc ... I recommend to use them with standard lines (20 m minimum) to keep most of its benefits that are : low end, smooth loops, forgiving kite.

[DukeSilver]

Thank you so much for the detailed answer. That all makes sense.

[TomW]

Hi Duke,

I'm new to foil kites and just got a HL 9m. I ordered it with 20+5 m extensions. It's fairly quick to change them. I've ridden kite with hydrofoil only 3 times. Sessions 1and 3 on 25 m, session 2 on 20 m.
I found kite good on both. Yes timing is more critical on 20m when down looping into gybe. But there's more wind on that session, so much more power too. Kite response is quicker, but actual turn is not that much faster.
When I was on 20m lines I was thinking, this is great, I'll keep 20 m on now.
Then yesterday it seemed light wind and it was changing a lot, up and down, so I rigged 25 m lines. It felt great! Down loops with gybe are sublime smooth and even power all the way around. I really enjoyed 40 min session until wind died.

My short experience is that 20 m and 25 m have definitely a place using this kite.

I should say that I started playing with 20 and 25 m lines on my North Monos my last trip to Cabarete due to high winds and I realised playing with line length to shorter has bigger effect than I realised. I think effect is exaggerated on Hydrofoil.

I might buy another foil and then I'll set up 2 bars, 20 and 25. Until then I'll just use the extensions.

[Mossy 757]

Pros:
More direct bar feel
Less wind drag on the lines
Faster redirect for transitions and jumps
Able to handle power more easily (biggest pro in my opinion)
Need less room to lay out and launch on a crowded beach
Cheaper to replace line sets if you make them yourself because you're using 25-35% less material than longer lines
Speculative: the wingtips are closer to the ground which can disrupt your wingtip vortices, providing some ground-effect which increases your L/D ratio at higher speeds

Cons:
Less torque created during power stroke due to shorter moment arm of lines (some loss of lowend riding for a given kite size)
Less time to recover from a collapse as the kite flies at a lower altitude
Timing changes from longer lines so there's an adjustment period
Easier to drag a wingtip in the water or fail to make a downloop during gybes, especially on very high aspect kites
Kite flies closer to the ground/water where there's more turbulence

[foilonfoil]

I have only seen the advantages of short lines (15M-16M) on the race course with high aspect ratio race kites - The Hyperlink is not a race kite. As a new foil kite flyer, focus on learning with the lines that come with the kites. You want to get used to the feel of the kite as it was designed.

Short lines also allow for larger surface area kites to be flown in the same conditions... 3M difference in lines is roughly 1M difference in kite surface area and flying with a larger kite helps with downwind runs which is especially important on the race course. For racers, its normal to have a full quiver of kites - 11/13/15/17/19 so its easy to rightsize the kite and lines to the conditions.

Learning to fly a foil kite takes time and one of the most important skills is learning to keep the kite moving/looping in lighter conditions... Short lines will only hinder this learning experience.

Anything beyond 18M is just personal preference. The standard lines on Flysurfer Sonic 2's is 21M and I use 18M-24M depending on kites and conditions.

[cglazier]

I switched from 24m to 20m lines for my 9m and 13m Chrono foil kites and am happy with them. Don't forget that the bridle on a foil kite is several meters long so the distance to the kite is not as short as you might think.

I tried 15m lines but I just couldn't get used to the quickness.


CG

[Flag53]

Hi all as a relative new comer to foil kites and foiling but not Kiting I recently bought a 12m Flysurfer Soul.
I messaged Flysurfer and they recommended 24-27m lines for ultimate light winds performance.
this was great info as in sub 8 mph winds I was up and running when two other guys on the new Moses 633 wings and inflatables ( a 15m breeze and a 18m gong ) where going no where.( I was on a Moses 550 / 325 combo )
The longer lines give it more time in the wind window and so more chance of getting going.
I guess it depends on the kite and how fast it turns and if it’s going to slow it down too much , but with the soul it’s no problem. Also as others have said it gives you more room for error when under looping the kite on foiling gybes.
I’m getting used to the soul now and because it’s so user friendly I’m rarely dropping it even in really light winds.
Why not message Ozone and see what they recommend!

[DukeSilver]

Thanks everyone for the great info. I'm not going to rush out and by shorter lines any time soon. I was just curious as to the benefits of shorter lines. I'll stick to my 22m lines for now.

[Pedro Marcos]

Pros:
More direct bar feel
Less wind drag on the lines
Faster redirect for transitions and jumps
Able to handle power more easily (biggest pro in my opinion)
Need less room to lay out and launch on a crowded beach
Cheaper to replace line sets if you make them yourself because you're using 25-35% less material than longer lines
Speculative: the wingtips are closer to the ground which can disrupt your wingtip vortices, providing some ground-effect which increases your L/D ratio at higher speeds

Cons:
Less torque created during power stroke due to shorter moment arm of lines (some loss of lowend riding for a given kite size)
Less time to recover from a collapse as the kite flies at a lower altitude
Timing changes from longer lines so there's an adjustment period
Easier to drag a wingtip in the water or fail to make a downloop during gybes, especially on very high aspect kites
Kite flies closer to the ground/water where there's more turbulence

For me the biggest reason for short lines its "having more control" when going fast, i think thats the outcome of: More direct bar feel, Less wind drag on the lines, Able to handle power more easily (biggest pro in my opinion) . So i guess that if someone is not looking for speed, he will be better in 20m lines, unless its super windy and he doesnt have a smaller kite.

I use 17m lines on R1V2 17m, 13m lines on R1V2 11m. On tubes kites i use 25-20m lines, i dont like their behaviour in short lines.