News about me and my family posted from my cellphone.
24 January, 2010
My Cyber4 wing as a Paramotor.
Hello everyone. It has been a while now since I have posted something about flying. Well, this weekend, I had a very nice and relaxing flight (1hour+) from Jeffrey's Bay to St.Francis Bay and back. The weather was perfect, with a slight onshore breeze, just right for my new wing. Icaro (the Cyber4 manufacturer) does not release any performance data regarding the wing. Armed with a GPS, Camera and Vario, I took off on the main beach in Jbay with the main intention of testing it as a paramotor wing. On take off, the wind was about 5-8Km/h. (On my first try it dropped to about 3km/h). The wing is heavier then my old Golden2 (and less performing). It come up just fine but did not give me the chance to turn around and run (I always do a reverse pull up). I waited a few more minutes and, when the wind got a bit stronger (around 5km/h), I tried again. It was a fairly slow pull up (normal for a very safe EN-A) and I did run like a dog. (Or at least it felt like that) At around 15Km/h I felt the wing been loaded and I knew I got over the most difficult part. I had a long stretch of empty beach in front of me and decided to back of the power slightly in order to test the behaviour of the wing during this most difficult part. While running at 13-15Km/h + a 5Km/h wind from the front, the wing was loaded to about 75%. I gradually pulled the toggles and I was surprised at the immediate response. Of course, the stall point was very close, at this slow speed, however, if my hands went fully up, the wing will respond by coming more forward. This wing is not meant for motorized flight to begin with. Is a very safe (probably the safest) paraglider wing there is. During this 'test run' I was impressed by the left/right response. A bit of pull and the wing will react. Keep in mind, it was only 3/4 loaded. Still, very responsive/sensitive for a beginner wing. By now I was getting tired of running (I am very unfit) and open the throttle to 100%. At the same time I put my hands up. In so doing, I wanted to see if it will just 'pick me off the ground' or should I say sand. Well, it did not. The speed was not quite enough, but very close. After a few more seconds of running, I did apply a very gentle and gradual brake, on both sides. As expected it picked me up in a flash and I come to realize, my feet were holding it back. On firm ground (not soft see sand) it will definitely 'get up' just by 'brute force'. At full power, it climbed steadily at around 1.4-1.5m/s, a bit slow compared to my old G2 (1.85m/s with the very same engine), but given its large size (certified 95Kg - 130Kg for paragliding!), I found it normal. However, shortly thereafter, out of nowhere, it began rolling. Not much, a few degrees either side. I remembered, ICARO tolled me, the wing is not meant for paramotoring and decided to back off the power a bit. The Vario dropped to about +0.5m/s and the rolling motion stopped. Now I wanted to know more about this anomaly. I knew the turbulence is zero because of the laminated air coming over the open see. Whatever motion there was, must be wing generated. I gradually 'powered up' again. The wing went back a little and as soon as the Vario indicated +1.0m/s the rolling motion began. I kept full power to see how bad it will get. It never went past 10 or so degrees either side and it responded very well to counter braking. (This has to be done at the right time, otherwise will make it worse). What bothered me more was the Hi drop in speed, while under full power. (Obviously Hands-up, NO brakes.) The large wing size relative to the total weight (about 120Kg all up) and low aspect ratio, makes for a safe paragliding wing but is not good for motoring. Next I wanted to see if the rolling motion is affected by the speed bar. Indeed, even 1/4 bar will reduce it a lot and at the same time, increase the speed to more normal/safe levels. I want to mention that only under full power this issue becomes troublesome. Anything below 1m/s climbing rate and there is nothing to worry about. Speedbar or not. OK, enough of this. With the engine fully stopped, my anemometer indicated a wind speed of 34.2 to 34.7KM/h. Nice indeed. Same test on full bar pushed the speed to 43.7KM/h. Not to bad for a beginner wing with a big cage and prop to block the wind. I think is safe to say, in a paragliding harness, you can add another 1-2Km/h to this figures. The hands-up sink was relatively Hi at 1.4-1.5M/s. While on quarter brake the sink dropped to about 1.3m/sec. The wing made a safe, solid impression, even for a beginner like me. Is reacting fairly quick when asked to but only for the first half of the toggle range. When you go past that is still does what any glider should do but less so. Not linearly. In other words is very forgiving. The low aspect ration certainly has a word to say regarding the safety, especially when the student wants to polish his boots with the toggles. In the end my GPS died (battery). The track log seems to stop in midair. Unfortunately it was here when I put it thru its paces (wanted the fuel tank to be almost empty). The landing was very uneventful, easy and predictable. (as expected of such a low spec wing) I will do some more testing next time. For now have a look at a few pics I took during the flight.