The radio components chosen were three Futaba S3114 micro-servos and the Futaba R617 FS FASST receiver (above left). The ElectriFly SS35 ESC has a 5V, 2-amp BEC, which saves the weight of an additional receiver battery to power the receiver and the servos. The rudder and elevator control rods (above
ter paired with a Futaba R617 FS receiver and three Futaba S3114 Micro High Torque servos. For those who expect to use a servo for each aileron, it just isn’t necessary for this ship. The single S3114 servo mounted in the center of the wing has plenty of torque for this airplane. The recommended ¹⁄₈ to ³⁄₁₆ inch up and down aileron movement; the ¹⁄₈ to ¹⁄₄ inch elevator movement; and the ³⁄₈ to ⁹⁄₁₆ inch right and left rudder throw do not tax these servos in any way.
Flying with the Wind The really fun part of any building or as-
sembly project is, of course, seeing the plane take to the air and take on a life of its own. The Cosmic Wind did not disappoint in any respect. With a projected all-up weight of be- tween 27.5 to 29.5 ounces, the plane came in on the lighter end of the scale at 28.2 ounces, with no additional weight added to arrive at the recommended c.g. of 2¹⁄₁₆ inches in back of the LE at the fuselage/wing juncture. I did balance it laterally as well, and
found that a small stick-on weight of a little over 4 grams was needed on the underside of the right wing. If you look closely at some of the photos you can see it as a small speck,
center) exit from their pre-installed tubes and line up perfectly with the S3114 servo arms. The tail wheel (above right) is mounted by way of a plywood plate and screwed to the fuselage. An L-bend in the tail wheel wire is buried and epoxied in the rudder for ground control.
which will be embedded in the wing tip lat- er on and covered with a piece of MonoKote. In order to get the necessary flight shots
for this article, I asked one of the better fly- ers in our local club, Paul Phillips, to do the honors while I manned the camera. I antic- ipated that a lightweight tail-dragger like the Cosmic Wind would have some problems with ground-looping on take off, particular- ly in our Oklahoma breeze. That was not at all the case. The little plane tracked straight down the runway with no need to keep the tail wheel pinned to the ground, and took off smoothly into a gentle, but steady climb at between half and three-quarter throttle. Once airborne, it required absolutely no trim changes whatsoever. It was delightful! It is a small plane and is a “burner” wide
open (It’s a racer, after all!), but it also slows down nicely with no tendency to drop a wing. Even though the recommended throws seem very small, they are more than adequate for loops, rolls, stall turns, and in- verted flight. While initial rolls were not en- tirely axial, a bit of rudder programmed in will fix that. The one anomaly that showed up from the first was in setting the plane up to land.
Most small models, regardless of their pow- er source, are not known for their glide. That is not the case with the Cosmic Wind. It is so clean and so lacking in parasitic drag that on its first landing attempt it was still sail- ing along merrily in ground effect as it ap- proached the end of the runway. A second go-around started the descent much further out and resulted in a smooth two wheel landing that dropped its tail to the runway as it lost air speed. While it doesn’t land as slowly as a trainer, anyone with trainer ex- perience will enjoy landing the Cosmic Wind. All in all, the project was most enjoy- able—from initially opening the box and dis- covering all of the high-quality components, to seeing the plane in flight and thinking about its racing origin as it banked around the field. One last precautionary note. This plane is not a park flyer. It needs space to fly and space to land. It is however, the kind of plane you can pull out of your car fully as- sembled on any day and have a great flying experience at your local field. Great Planes is to be congratulated on a job well done in adding the Cosmic Wind to its stable of great flying airplanes.
Even at this angle it is easy to see that ElectriFly has captured the lines (above) of the original Cosmic Wind nicely. Even though throw setups on the controls seemed to be very small compared to most planes, they were sufficient to allow the plane to do any sport aerobatics within a very small envelope (above right). At the same time, the plane is a burner when opened up to max throttle, yet lands not much faster than a trainer (at right).
FLYING MODELS 41
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