Sizes Available: 6, 7, 8, 9, 10, 12, 14m
Sizes Tested: 9, 12m

Airush Says:

The Union v4 has been re-designed from the bottom up to improve key areas, delivering even more lift and hang time when going for big air, along with quicker and more responsive steering. The shape has been refined to sit slightly further forward in the window whilst retaining the light and ultra-responsive steering. The wingtip design prevents back stalling, while the increased linear power delivery has made it even more suitable for freeriding, freestyle, and wave riders alike.

The Union is the natural step up for the Lithium user looking for increased high end jumping performance and more forward steering. Ideal for the freestyle rider wanting unhooked performance and a more forgiving feel. For a more direct response and totally fresh feel, the new fixed bridle adds another dimension for an intermediate to advanced rider. It offers a direct response and uses less bar input for immediate steering and more crisp feel for improved kite looping.

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Our Testers Say:

“Smooth turning kite, smooth power delivery, great performer on all fronts, friendly in the air with plenty of power.” // Joe Chehock

“Quick kite response, predictable, bar pressure just right to feel the kite w/o being tiring. A pocket ace for the intermediate and advanced rider who expects predictable, quick kite response and solid boosting and easy relaunches.” // Tib Anghel

“Diagonal canopy supports for folks expecting many years out of a kite. Nice, light feeling, flat LE with excellent boosting performance and good turning speed and great upwind ability.” // Dylan Dobbyn

Meet Our Testers

TKB Says:

The Union v4 is Airush’s explosive boosting big air lift freeride kite that Airush markets as the next step up beyond the Lithium in the freeride category. With its 3-strut airframe and medium to higher aspect canopy with square wingtips the Union earned Tester’s respect as a user-friendly yet high performance boosting machine. The leading edge feels fairly slim and the overall weight of this kite is impressively light while still using the Dyneema load frame construction. The Union features a fixed single setting leading edge bridle for direct steering and power response and three wingtip settings to select between more/less bar pressure, which we rode on the stock less bar pressure setting at the end of the wingtip. The Union’s wingtip pigtails end in knots and the leading edge bridle ends in loops and the Union came with a Boston valve which requires the larger of the standard hose fittings that come with all pumps for a quick and easy inflation. The Union is one of those performance freeride kites that you can feel likes to fly a little bit farther forward in the window and when you get a gust this kite really likes to accelerate and build more and more power, the kind of power you can turn into vertical lift. We were really impressed with this kite’s boosting power, making jumps really fun with good hangtime. In terms of steering response this kite has a fairly direct feel and the steering arc is a bit wider than both the Lithium and the Wave, both of which feature a more pivotal steering path. The Union’s steering is one of the qualities that make this kite such a strong, big air lifting machine. Tester found the Union to have medium bar pressure with the power delivery being fairly progressive, but not as sheet and go as what you find with the Lithium. The Union wants to be flown a little more aggressively but the power delivery across that throw is intuitive. In terms of relaunch the Union delivered a steady relaunch every time. Nose down in the water at the bottom of the window, with a solid pull on the kite it rolled up onto a tip and began to taxi towards the edge of the window. Unlike the Wave, the Union did not hot launch from the bottom of the window, but reliably released its wingtip at the edge of the water. Based on tester feedback, the Union could double as a progression kite for a more aggressive beginner, but ultimately this kite is the bread and butter of a freeride kiter looking for explosive boosting power that also offers a very intuitive feel and is fairly user-friendly. We’d consider using this kite in the waves for the odd session, but its primary place of use would be big air/performance freeride and scoring a spot on the Woo scoreboards. Overall, the Union is an excellent choice for big air specialists that also demand user-friendly all around ease of use.

The Union came with two types of bars, the Core Bar V4 and the Core Cleat Bar V4. The Core Bar comes with the above the bar power straps for adjusting depower and the Core Cleat Bar which features an above the bar cleat for adjusting power. The Core bars are largely the same except for the power management mechanism for powering and depowering the kite.

The Core bar V4 is an adjustable length bar (50-60cm) that features a single center-line safety flag depower with a low V and a reduced diameter PU-coated depower/throw line for durability and longevity. The center lines end in knots (color coded blue) and the outside lines end in loops (color coded red and white). This bar features a sliding stopper to adjust travel, yet there is no adjustment for changing the overall length between the quick release and power control. The Cleat Bar features Velcro on the power tuning toggle to keep extra slack in place while riding and the above the bar power straps are always kept in place and within reach. These bars feature a below the bar hand swivel integrated into a push away quick release with a quick release travel guard. To trigger the quick release simply use one hand to slide up the square shaped release handle but when it comes to resetting the quick release it is a two-handed process. One hand has to hold the release handle in the open position, the other hand has to thread the pivoting gate through the end of the loop and then back into its closed position before releasing the handle to slide back. Last year we felt the swivel wasn’t that easy to move, yet this year the swivel seemed much more easy to rotate.

You can adjust the length of the outside lines by folding over the integrated floats and removing the internal leader lines out through a hole in the floats. Adjusting the outside line lengths is done by connecting to one of three knots (the stock setting is the shortest setting). The bar diameter is thin and offers medium density cushiness – it has a ton of texture with ridges, and grooves that create a grip pattern that is fairly diverse. Your hand will get accustomed to the proper feel of the bar in your hand and likely discourage accidental bar reversal. In addition, the smooth aluminum insert is labeled with an Airush logo when the bar is properly held, and when the bar is reversed you see ‘wrong way.’ The bar ends are rubbery for accidental facial contact and the floats are integrated into the bar ends and very helpful when grabbing extra tension on the outside lines. New this year, the bungee is tucked into the float and is semi retractable which means the bungee stays out of the way while riding and wrapping, but are useful for clean stowage when the bar is not in use.

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With the help of 14 testers from all walks of kiteboarding, Tkb’s staff assembled detailed gear reviews with objective performance criteria of the latest 2019 kites, twin tips and foilboards all packed into one neat and tidy 180-page digital package. Get all the reviews in convenient digital guide here:

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