PARAMOTOR WINGS      I've been testing some wings with the view to finding a good wing for paramotoring. I have learnt the hard way (I've just bought my fourth wing) that the requirements for a paramotor wing are quite different than for free flying. Initially I used my performance freeflying wing. It was fine for reverse launching on the coast, and flying in smooth air but was too difficult to forward launch and unenjoyable when it got rough. When I bought my second wing (Santana 25) I only had the opportunity to test how it forward launches. My previous wing, an Airwave Fusion, had gone dangerously porous (Porcher Marine fabric) and wouldn't forward launch with the motor in nil wind on flat ground at all. I assumed that any DHV1-2 wing would be good for paramotoring and all I needed to check was how easy it forward launched. Forward launching in nil wind on flat ground is the most difficult part of paramotoring. My naive assumption was an expensive mistake, as stability under power is also very important. Paramotors under power fly at a higher angle of attack than when gliding. Some wings can be wonderfully stable at gliding angles of attack but can be unstable under power. In Germany wings need a special certification for paramotoring. For a start there are two different types of wings that are used for paramotoring. Wings such as the Reflex and Silex were designed specifically for paramotoring. They are generally fast and stable but have a high gliding sink rate which increases fuel consumption. Speed is important on a paramotor as we so often are flying against a headwind. Paraglider wings with their better sink rate and fuel consumption are also commonly used. Some paraglider manufacturers produce paramotor versions of one of their wings. This usually is different only in that the risers are shorter to compensate for the higher attachment points and have trimmers. It can get very tiring punching headwind for an hour on speedbar. I was given an APCO Fiesta and a Swing Arcus on trial which I tested over two and one week. Both can come with paramotor risers, although the wings I tested didn't have them. I tried them both alternately in varying conditions multiple times until I was fairly sure of their characteristics. The Fiesta is DHV1 in all sizes even on speed bar. The Arcus is DHV1-2 in all sizes with and without speed bar, except the medium which I flew, which is DHV1 without speedbar. The Fiesta comes in four sizes, the Arcus, three. I was lower on the weight range on the medium Arcus than on the small Fiesta (second size of four). Unfortunately I never got enough nil or very light wind to adequately test how they both forward launched. Also living on the coast I don't get much nil wind, so my forward launches are not very experienced. However I tried to simulate forward launching by wearing the paramotor harness with it's high attachment points and without the motor. I then clipped in backwards so that I could hold my hands where they would be for forward launching but I was reversed and could watch the wing as it came up. I spent about two or three hours pulling up both wings repeatedly and alternately. The Fiesta is more likely to drop back when ground handling and pulling up. This is probably the other side of the compromise that makes it less likely to overshoot on pullup. The Arcus was more likely to overshoot and fold a side of the wing under. The Fiesta was less sensitive to holding the "A"s down too far for too long and hence causing a frontal collapse. The Fiesta didn't respond quite as well to steering it up by varying pressure on one "A" or the other. To test their stability I would fly in strongish wind 12-15knots and see how low I could comfortably fly. The turbulence near the ground is more repeatable than trying to use thermals. The Fiesta is incredibly pitch stable but can roll a bit more in turbulence. The Arcus is less pitch stable and would sometimes pitch back and up quite a bit when hit by a gust. Both wings were noticeably more stable in level flight than my Santana or Fusion. I found I could fly lower in stronger wind then I had thought safely possible. Thermalling both wings with the motor was a dream. The Fiesta having the higher brake pressure while thermalling. The brake pressure on the Arcus just keeps increasing and it actually required a wrap and the higher brake pressure to make it spiral. The Arcus looks and feels like a higher performance wing than the Fiesta. The Arcus is more aspecty, has more cells and has diagonal bracing in the wing, which the Fiesta doesn't. I couldn't compare sink rates and L/D but this is not as important as for free flying, as even when turning off the motor you can (hopefully) restart if you're likely to bomb. I tested airspeeds with the GPS by flying straight headwind and downwind in level flight on the coast, adding both ground speeds and dividing by two. Both wings had trim speeds of 34kph. Full speed system gave 42kph on the Fiesta and 45kph on the Arcus. Note that these speeds are lower than for gliding due to the increased angle of attack (less likely to collapse). The Arcus has a lot more travel on it's speed system. I didn't try the paramotor risers but I would still expect the Arcus to be the faster with trimmers etc. The Fiesta had a slightly greater tendancy to turn right due to the propellor torque. (P factor) The Arcus had amazingly little tendency to turn right. I went free flying on both wings on a coastal site to try sixty degree wingovers then releasing the brakes at the highest point of bank. Both wings were increadibly stable and would just return to normal flight without over shooting (unless I leant in the opposite direction). I pulled on collapses (on trim) and both wings were equally mellow in their response (the medium Arcus I flew is DHV1 also). A collapse close to the ground on either of these wings would be about as safe as a paraglider could be. Considering flying close to the ground is one of the most fun aspects of paramotoring this is important. The Fiesta feels a bit more like a truck than the Arcus in that it is a bit more sluggish in turns etc. My personal opinion is that a truck is the best type of wing to first experience inland flying, as things happen more slowly, it is harder to overcorrect, and more forgiving of errors. My first hang-glider and paraglider were both trucks. The biggest disadvantage of the Fiesta was it's behaviour with full throttle. It would often build up a roll oscillation where the wing was moving from side to side above me by about two metres. It could not be damped with the brakes. It was necessary to ease off on the throttle for the oscillations to die down. However I prefer not to run the motor flat out on long climbs anyway. With heaps of thrust the Arcus wasn't as stable as it was in level flight, but it only rarely oscillated in roll. Some insight into some of the propellor effects on paramotors can be found at www.xplorer.co.za/articles/ . There are also other informative technical articles on paramotors at this site. Although it doesn't specifically mention this effect (as my propellor is vertical when I hang up in the harness) it does mention a similar effect called asymetric blade thrust. It is possible that this effect won't occur with other motors and harness configurations. Also I am a little bloke with quite a powerful motor. So heavier pilots on the same motor may hardly notice it. Although the fact that it hardly happened at all with the Arcus shows that the Arcus is less sensitive to it occuring. The biggest advantage of the Fiesta is that it is made of Gelvenor double silicone coated fabric. This means it will last a lot longer than other wings. Jean-Luc's APCO Futura has 550 hours of mostly coastal flying with sand and salt, but it still looks good and is very non-porous and tear resistant. You won't have to worry about the fabric when laying the canopy out on dewey grass for the early morning glassy air, or packing up after sunset. You will still have to worry about line shrinkage though. The biggest advantage of the Arcus is an extra 3kph of top end speed. Having found myself in situations with kilometers to fly headwind but with a ground speed of only five to ten kilometers per hour, 3kph can be heaps. However collapses at full speed have a DHV1-2 rating on the Arcus and DHV1 on the Fiesta. Colapses on a paramotor are less fun than when free flying, although they are less likely under power due to the higher angle of attack. I have 500 hrs on paragliders and fly a high performance Bagheera for free flying but prefer something much more mellow for paramotoring. The Arcus has also been getting good reports as a paramotor wing on the internet. I bought the Arcus. Another wing I looked at is the Ozone Electron (DHV 1-2). A few months ago I tried one for a couple of short motorised flights. It too seemed very stable under power, but I didn't get the opportunity to really put it through it's paces. It too is made of Gelvenor fabric, although the silicone coating doesn't feel as thick as it is on the Apco wings. It's definately another wing worth test flying. I'm using an Apco stuff bag for my paramotor wing. This bag is interesting in that it is almost flat with a cord thru eyelettes around the edge. When I am packing up my Arcus after sunset (wing can feel a little damp) I just throw the bunched up wing on top of the spread out bag and tighten the pull cord. When I get home I loosen the pull cord to let the bag flop flat and fluff up the wing a bit and leave it to air.