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Flat LEI Foil or Bow Kite? Best Types Of Kites

It all started with a simple discussion on the Kitesurf group back in 2003 regarding “Fully Sheet Out Kite” which allows kiters to fully depower the kite. The whole discussion was about being able to sheet out or depower a classic LEI completely by adding a bridle system on the leading edge.

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However, years passed, the technique developed, and new types of kites emerged on the market. Thus, the question remains, which type is best and under what conditions?

Classic LEI Kites vs. New Bow Kites

Bruno Legainoux, the inventor of the classic LEI, took the bridle on the leading edge concept further and filed a patent application in French on 2004/03/01, in Canada and in the US on 2005/02/28 (Canadian Patent Application number CA 2498729, US patent application number 11/067,0842) for a kite design that incorporated a bridle on the leading edge with a flat, swept-back profile and concave trailing edge.

The result of Bruno’s design was the new bow kites as introduced by Takoon and Cabrinha as the Nova and Crossbow in 2005. The early bow kites, while allowing them to be depowered fully, have a number of disadvantages compared to the classic LEI:

  1. The kite can get into an invert position and can’t fly properly.
  2. It is a bit twitchy (like foil) and not as stable as the classic inflatable.
  3. Pretty heavy bar pressure.
  4. Pretty difficult to relaunch.
  5. Lack of “Kite Sled Boosting” effect when jumping.

Bow or Non-Bow Leading Edge Flat Inflatable Kites

Since then, both Bruno and other designers have improved the original generation of bow kites and introduce a new generation of flat Inflatable kites (Flat LEIs) that may or may not use Bruno’s design. Those Flat LEIs are apparently so excelled in safety, performance, and ease of use that they created a major stir in the kiteboarding market. The main differences between the ones that use Bruno’s design and the ones that don’t are:

  • The bow Flat LEIs (bow kites) have a concave trailing edge. The non-bow Flat LEIs (Supported Leading Edge) don’t have a concave trailing edge. Most are straight, some even convex. 
  • The bow Flat LEIs tend to be flatter,  the non-bow Flat LEIs tend to have more depth and therefore have more “Sled Boosting” effect.

This flat kite had a flat or convex trailing edge (different from the original bow kite).

The same kite in flight. The front bridle is more forward and completely separated from the back lines. The kite is not as flat as the original Bow and therefore has a more “Sled Boosting” effect. 

Flat LEI vs. Bow Kite

  • Don’t invert easily as the original bow kites (the less flat the kite, the less invert tendency)
  • Not as twitchy as the original bow kite
  • Can fully depower (very safe for beginners and all kiters)
  • Light bar pressure, similar to classic LEI (no complex pulley system is needed)
  • Very easy to relaunch (sometimes even easier than classic LEI with 5th line)
  • Very easy, safe self-launch and self-land (easier than classic LEI)
  • Has a similar “Sled Boosting” effect as classic LEI (the flatter the kite the less “Sled Boosting” effect it has)
  • Better L/D ratio than classic LEI therefore faster

Furthermore, a newer generation of Flat LEI called “Hybrid” started appearing on the market. These newer Flat LEIs are more or less the hybrid of the traditional LEI and the Flat LEI.

Flat LEI Foil Kite Bar

Flat LEIs require the use of bars with a longer trim strap and longer chicken loop to be able to fully depower the kite. Even with the ability to fully depower the kite, the kiter should also have a safety leash connecting to one of the front lines or rear lines as in traditional bars.  Following is a diagram of a typical Flat LEI bar:

Kitesurfing With a Flat LEI Is Safer

Compared to the standard LEI, flat LEI kites are much safer. One can fully depower the kite while it is sweeping across the power zone. If you have a chance to test drive a new flat LEI kite, try to fly the kite across the power zone and then depower the kite (fully extend your arms or drop the bar). If a flat LEI kite does not drag you at all, it is a fully depowerable kite.

While a safety leash is still recommended and necessary, some experienced kiters don’t rig a safety leash on a fully depowerable flat kite and use a safety handle (attached to a front or rear line) when things go wrong. 

There are enough incidents that happened locally to convince us that a safety leash is still mandatory for Flat LEI (at least a safety leash that simply attaches to the chicken loop).

The Future of Leading Edge Inflatable Kites

Which such characteristics, the flat LEIs will have a major impact on the kiting world.  We anticipate the following impacts:

  1. Kitesurfing will be safer as the kiter can just let go of the bar
  2. Kitesurfing will be safer as launching and landing are safer
  3. Kitesurfing will be safer as the kite can handle gusty wind better
  4. Learning will be easier (very easy to relaunch) and safer
  5. No need to body drag upwind, just depower completely and swim back to the board
  6. Bar design becomes much simpler and all are spinnable (the safety leash can simply attach to the chicken loop)
  7. Even unhooked bar are simpler and spinnable
  8. Very wide wind range per kite, need fewer kites per kiter
  9. Higher performance kites, kiters can probably break the out-right speed record.
  10. Easy boat launching and better power handling for kite-boating.
So far the annual of Flat LEIs have surpassed the sales of traditional inflatables.

The Best Kite 2021?

They say that this is the ultimate kite that “does it all”, regardless of whether you are a beginner or advanced kiteboarder. What do you think? 

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