After flying all their models, after visiting with company representatives on several occasions, and after visiting the factory in Aubenau, France, I feel like I know the Air Création people. So I should have known they wouldn't just make a new wing purely for marketing reasons. Indeed, when I few the iXess after flying their new Fun 450 wing (also reported in this article), I came away with that same head-shaking-in-wonder feeling that has affected me before. I know a little something about delta wing design, having been around hang gliding since the early 1970s, and trikes since their beginning. That helps me to comprehend how far these wings have progressed and how much harder it is to extract additional gains year after year. Trike wings (and hang gliders) generally trade more glide or speed performance for handling ease. At least, that was how it used to be. Today, that statement must be modified to reflect the surprising capacity of modern wing designers to find more performance at the same time they refine the handling. In short, the iXess is a triumph of cultured wing design that sends notice to every other developer. If you stumble over the name, don't feel alone. Many folks don't know quite how to say it. American importer John Kemmeries explains that iXess is pronounced EYE-excess. Tale of Two Wings This article will focus on the deluxe Clipper 912 with the iXess wing, but that isn't the only new chariot Air Création debuted in 2004. They also introduced their first 2-place Fun chassis fitted with the enlarged Fun 450 wing. Most Air Création followers know the Fun 14 wing paired with the single-seat Fun Racer trike. The "14" refers to square meters (150 square feet). Now, the factory has increased the range to the Fun 450, a larger, 17-square-meter, mostly single-surface Fun wing. It is mated to a Twin carriage, a long-standing 2-seat tandem cart from Air Création. What I'm describing is the first Fun for two people (see sidebar, "More Fun for Two People"). This covers one end of the trike-buying spectrum. The other end is the Clipper 912 with the iXess. Interestingly, the same wing structure is used inside the Kiss, iXess, and Fun wings Air Création produces today. This simplifies the effort of manufacturing and eases parts supply at dealerships. And it shows that the art of delta wings is not in the frame, important as that is. The larger share of what makes the wing work is the sailcut, rib patterns, and numerous little refinements that improve handling and speed range at the same time. One such example involves the use of 7075-T6 alu minum tubing on the forward leading edge, the crossbar, and the ribs. This is a strong, more rigid alloy that can be used with thinner walls (to a point) without sacrifice. However, its rigidity stands in the way of lighter handling, so more-flexible 6061-T6 aluminum is used on the aft leading edges to permit more sail shifting. Air Création designer Gilles Bru showed me a construction at the leading/crossbar junction, which allows the use of thinner wall tubing than was possible with the previous brackets. Where once long bolts and beefy brackets were used, now a small, lighter set of custom hardware does the job (see photo, "INSIDER VIEW"). As with top hang glider designers, the cloth material on the Fun wing is carefully chosen. For the Fun wing, very dimensionally stable Trilam is used on the leading edge where more flexible Hydranet is employed for the main sail body. Air Création likes Hydranet as it does not propagate a tear should, for example, a rock be thrown up by the wheels or prop. On the more sophisticated iXess, the entire sail is made from Trilam as it suits higher speeds better. The iXess also has a cloth doubler on the trailing edge due to stress from a tautly stretched wing. On the Fun 450, the trailing edge is merely hemmed. To help maintain the fine handling of the Kiss wing, a portion of the iXess undersurface uses spinnaker cloth, a modestly lighter cloth with more yield. The more flexible cloth keeps the relationship between upper and lower surface more elastic to help with handling and low-speed flight characteristics. The concentration of spinnaker cloth is at mid-span where it can do the most good. From the crossbar leading edge junction toward the nose, a PVC plastic material is used to smoothen and retain the shape at the leading edge; this helps the iXess retain the speedy ways of the XP series. More common and less rigid Mylar is used on the outer portion of the wing; this change of materials is another subtle aid to turning qualities. Due to their experience with the DHV test vehicle, Air Création has been able to eliminate the older-style tip After flying all their models, after visiting with company representatives on several occasions, and after visiting the factory in Aubenau, France, I feel like I know the Air Création people. So I should have known they wouldn't just make a new wing purely for marketing reasons. Indeed, when I few the iXess after flying their new Fun 450 wing (also reported in this article), I came away with that same head-shaking-in-wonder feeling that has affected me before. I know a little something about delta wing design, having been around hang gliding since the early 1970s, and trikes since their beginning. That helps me to comprehend how far these wings have progressed and how much harder it is to extract additional gains year after year. Trike wings (and hang gliders) generally trade more glide or speed performance for handling ease. At least, that was how it used to be. Today, that statement must be modified to reflect the surprising capacity of modern wing designers to find more performance at the same time they refine the handling. In short, the iXess is a triumph of cultured wing design that sends notice to every other developer. If you stumble over the name, don't feel alone. Many folks don't know quite how to say it. American importer John Kemmeries explains that iXess is pronounced EYE-excess. Tale of Two Wings This article will focus on the deluxe Clipper 912 with the iXess wing, but that isn't the only new chariot Air Création debuted in 2004. They also introduced their first 2-place Fun chassis fitted with the enlarged Fun 450 wing. Most Air Création followers know the Fun 14 wing paired with the single-seat Fun Racer trike. The "14" refers to square meters (150 square feet). Now, the factory has increased the range to the Fun 450, a larger, 17-square-meter, mostly single-surface Fun wing. It is mated to a Twin carriage, a long-standing 2-seat tandem cart from Air Création. What I'm describing is the first Fun for two people (see sidebar, "More Fun for Two People"). This covers one end of the trike-buying spectrum. The other end is the Clipper 912 with the iXess. Interestingly, the same wing structure is used inside the Kiss, iXess, and Fun wings Air Création produces today. This simplifies the effort of manufacturing and eases parts supply at dealerships. And it shows that the art of delta wings is not in the frame, important as that is. The larger share of what makes the wing work is the sailcut, rib patterns, and numerous little refinements that improve handling and speed range at the same time. One such example involves the use of 7075-T6 aluminum tubing on the forward leading edge, the crossbar, and the ribs. This is a strong, more rigid alloy that can be used with thinner walls (to a point) without sacrifice. However, its rigidity stands in the way of lighter handling, so more-flexible 6061-T6 aluminum is used on the aft leading edges to permit more sail shifting. Air Création designer Gilles Bru showed me a construction at the leading/crossbar junction, which allows the use of thinner wall tubing than was possible with the previous brackets. Where once long bolts and beefy brackets were used, now a small, lighter set of custom hardware does the job (see photo, "INSIDER VIEW"). As with top hang glider designers, the cloth material on the Fun wing is carefully chosen. For the Fun wing, very dimensionally stable Trilam is used on the leading edge where more flexible Hydranet is employed for the main sail body. Air Création likes Hydranet as it does not propagate a tear should, for example, a rock be thrown up by the wheels or prop. On the more sophisticated iXess, the entire sail is made from Trilam as it suits higher speeds better. The iXess also has a cloth doubler on the trailing edge due to stress from a tautly stretched wing. On the Fun 450, the trailing edge is merely hemmed. To help maintain the fine handling of the Kiss wing, a portion of the iXess undersurface uses spinnaker cloth, a modestly lighter cloth with more yield. The more flexible cloth keeps the relationship between upper and lower surface more elastic to help with handling and low-speed flight characteristics. The concentration of spinnaker cloth is at mid-span where it can do the most good. From the crossbar leading edge junction toward the nose, a PVC plastic material is used to smoothen and retain the shape at the leading edge; this helps the iXess retain the speedy ways of the XP series. More common and less rigid Mylar is used on the outer portion of the wing; this change of materials is another subtle aid to turning qualities. Due to their experience with the DHV test vehicle, Air Création has been able to eliminate the older-style tip struts. They are not as effective in high-load, high-speed situations when they can bend downward. Instead, designers use pitch lines or luff lines further out on the wing, to about two-thirds of the span. These lines, running from the kingpost, impart some wing reflex when loads increase. Air Création believes the lines are superior to the tip struts because the more load the wing is seeing, the more effective are these lines. The new iXess wing is only made in a single size thanks to its versatility. Yet the Air Création trimmer system further extends usable speed range. The wing can handle 450 kilos, or 992 pounds, of load and the entire aircraft is tested for limit loads of +6, -3 G. Squeezing the extra handling and performance is no small challenge. Even the experts take time to get it right. Development of the iXess started in 2000, yet it was not seen in the U.S. market until 2003. The iXess wing uses nine lower ribs, with somewhat wider spacing at the tip to allow more shifting of the wing for improved handling - the way the sail and airframe move relative to one another is what allows a delta wing to respond so well to weight-shift control inputs. The upper surface of the iXess has 13 ribs to maintain a precise airfoil shape. In all, 44 ribs go into the iXess wing. Bru prefers to say, it has "a lot" of ribs. Air Création claims top honors in competition with the iXess wing. In preproduction configuration, the wing helped secure a first-place win at the 2001 World Championships and repeated this finish at the 2002 European Championships. Superb Clipper Air Création trikes have been painted red as long as I've known the company. The choice may be smart. Leading executives of automobile companies say red is the best color for marketing. When Air Création introduced the Clipper chassis, they added to the fairing surrounding the cockpit, and added a color. A tasteful gray or silver lower surface is separated from the company classic red by a black pinstripe. The only change from the earlier Clipper models, due to the larger engine, is the Clipper 912 logo on the side. The model still uses the little windscreen that someone once called "a windshield for your knees." In reality, the fiberglass nose easing smoothly to the tinted windscreen moves most of the air around the front occupant. However, the windscreen does little to protect your face; therefore my recommendation, and the practice of the factory, is that you use a full-face or pull-down visor helmet. Three options appeared on my test aircraft and that's saying something since the model is very well-equipped as part of its base price. One item is purely cosmetic or style oriented. The lower surface of the iXess has a custom color treatment that you must pay extra for but through this means you can personalize your aircraft. More functionally, steering for the rear seat along with a rear-seat foot throttle will help if you give rides or lessons with the new pilot up front. If you rarely do this, you'll have little call for these options. The test machine had Air Création's very slick trimmer system, or simply aerodynamic trim, of another sort. On tailless wing trikes, conventional trim won't work and you cannot use a stick reposition system like Quicksilver, Sonex, or others use. Trikes use a series of luff lines or pitch lines that hold up the wing's trailing edge when the rest of the wing draws tighter or forward. Like regular trim, this is sufficiently subtle that you might not notice the movement, but you'll notice the relief on the control bar. Since the Clipper body fairing is built over the Twin chassis, the interior of the Clipper 912 is familiar to 2-seat Air Création pilots. Along the seat frame you'll find the hand throttle console on the right. Under this plastic housing are the kill switches, thoughtfully located so you don't inadvertently bump them to the "off" position. The Clipper 912, with that big 4-stroke 4-cylinder engine, adds a carburetor heat switch on the left side and a choke control approximately at the front occupant's shoulder on the right side seat rail. Air Création "rudder pedals" are used to steer the aircraft on the ground, via the often-maligned but quite workable push-right/go-left steering. In fact, trike steering is similar in operation to bicycle or motorcycle handlebars, or snow skis. Air Création's pedals are large, offering good foot support (partly so you don't rest them on the fairing floor). The right pedal pivots as a spring-loaded throttle for takeoff and landing. The left one operates the nosewheel brake. I was pleased to have recoil three-position seatbelts for both positions. And while this particular rig was not equipped with a ballistic parachute, the company sells so many of them that they are one of a few companies to develop and incorporate an automatic engine kill switch into the rocket motor's pull handle. In Air Création's case this was done in cooperation with BRS engineers to assure proper execution. Having such a switch saves the pilot one vital step. Nosewheel brakes aren't known for their stopping power on trikes due to the light nosewheel loading. So I was surprised by the very strong braking power on the Clipper 912. On the downside, when turning, it is easy to activate the brakes so you must concentrate on steering with your heel. Rocket Launch Takeoff Bru suggested that I take off and land with the trimmer in the zero position. The trimmer marks are very easily understood in any language, appropriate for a French company selling around the world. His advice may have been offered because the wing handles more predictably in this setting, important in such critical phases of flight. It also helps you keep your speed in the correct range. Setting the trimmer to neutral may also be useful to help contain that big engine driving you into the air. I flew solo and after the first launch, I never used more than about 60% power to get aloft. Density altitude was only about 1,500 feet despite the heat and humidity, but I can envision high elevation sites where 81 horsepower may be necessary. Two-place flying with big American occupants could be another reason. Of course, you'll pay for this engine much more dearly than the Rotax 582. Despite the substantially heavier Rotax 912 engine and despite a fairly wide cockpit fairing, I found the iXess handling to be very good, even flying solo. My experience suggests the larger XP-17 wing does not handle nearly as well on the Clipper 912 chassis as the iXess. The XP wings are great for cruising but the large model was pretty heavy in roll. The versatile ways of the iXess on this carriage are significant enough to eliminate the need for a second wing size. Since the trimmer results in a repositioning of the control bar, I found the handling was actually better when the trim was set to high speed as this meant I did not need to pull aft on the bar with as much effort; it was already further aft. When trim was set to slow, I had to pull aft to help accelerate into the turn. Such is a common trike motion: pull in, shift to the side, and push out. It has been called the "J" stroke and pushing out is similar to holding backpressure on a control stick in a 3-axis airplane. This is probably why Bru encouraged me to approach for landing in the neutral trim position, to facilitate better control. Bru also says the iXess wing does not perform or handle much differently whether one or two people are on board. I can hardly overemphasize what an accomplishment this wing design represents. Bru says the Fun 450 Fun wing travels 40 to 100 km/h (25 to 62 mph) when flown solo, ranging to about 120 km/h (75 mph) when flown dual. My experience was nearly identical to his statement. Conversely, the iXess wing has a range of about 50 to 140 km/h (31 to 88 mph), dual or solo. Maximum dive speed with no power in the Clipper 912 indicated 72 to 75 mph when the trimmer was left in the neutral position. Thinking back to trikes in the 1980s (most of which maxed out at perhaps 50 mph), this seems a blazing speed achievement. Trim speed in the neutral setting was about 58 mph. When the trimmer was turned all the way to the slowest setting (tighter luff lines), speed dropped to 47 mph; conversely, when turned to the faster (looser) position, speed rose to 64 mph. Turning the trimmer to slow tightens the luff lines pulling up on the trailing edge, which creates more reflex at the trailing edge, raising the nose, and thereby slowing the aircraft. Going the other way loosens the lines, which allows the wing to flatten and fly faster. With the trimmer in the fast position and pulled in for maximum nose-down at nearly full power, I was able to produce an indicated speed of 83 mph, very close to what Gilles had promised. The difference may be no more than instrument error. Beautiful Behavior Turning to the slow end of the range, the iXess wing never broke over in stalls even with the control bar all the way out to the forward support tube, as far as I could reach. Even on a bumpy day, the trike was highly stable throughout the stall routine. I did my usual routine of power-off, full power-on, and accelerated stalls in each direction at 40° to 45° of bank. Always, the machine behaved perfectly. I measured descent rate at 500 to 600 fpm with the engine at idle. Bru thought that sounded a little high and suggested that if I'd slowed down further, as I'd considered, that the rate of descent would have been lower. I had conducted my test in the neutral trim position with my hands off the bar (so about 58 mph). In the slow trim position (about 47 mph), the descent rate might have dropped by 100 to 200 fpm, he thought. Talking about the performance range of the iXess, Bru wanted me to mention the overall efficiency of the wing design, and I can say unequivocally that I find it to be their best wing yet. I've flown the smaller and larger Fun wing, the Mild 16 wing, the 11-, 12-, 15-, and 17-square-meter XP wings, the Kiss 13 (square meter) and 450 (kg) wings. After all that, I find their best work to date is the iXess. Though I've been around hang glider designs for more than 30 years and understand all the developments they've been through, I'm still amazed at how these talented designers can squeeze ever-better performance out of the wing while improving the handling. In general thinking of delta wing design, you can increase performance or improve handling, but not both at the same time. The Kiss wing was an excellent handling improvement and the iXess does it one better while retaining the speedy characteristics of the XP series. Put it together with the elegant and comfortable Clipper 912 chassis and my ending comment is, "Bravo, Air Création, bravo!"