Art Hobby: Elster HLG: Exceptional prebuilt glider

Art Hobby: Elster HLG: Exceptional prebuilt glider

Loud, Richard

In German, “Elster” is the word for a bird we know in the U.S. as a magpie. In model aviation, the Elster is the latest 1.5– meter, 80-percent prebuilt hand-launhed glider from Art Hobby and distributed by Global I lobby Distributors.

Hand-launched gliders are a relatively new addition to the arsenal of the RC sailplane pilot. When I built my first Gentle lady back in 1980, all we had to choose from were built-up– wing polyhedral thermal ships. Things have come a long way; now we have a sailplane type for every flying condition, and hand-launched gliders (HlGs) are one of the few types of model that every carious sailplane pilot always has with him.

Opening the box, I was amazed by the craftsmanship of the wings; they’re presheeted with black poplar veneer. I later read the box cover, on which the wings are likened to a fine musical instrument. I think a master violinmaker would be proud of them. I set aside the glorious wings and found a very complete, well-thought-out kit-front the painted fiberglass fuselage pod and carbon-fiber boom to the prehinged V-tail halves, the kit included nearly all the required hardware. All it lacked were threaded rods and devises for aileron pushrods and hinge tape for the ailerons.

There isn’t a lot to constructing the Elster. According to the plan, the first step is to make a fuselage assembly jig out of scrap balsa and it flat board or a piece of cardboard. I considered skipping the jig but realized that it was so simple to make, it would be foolish not to do it. It was also a good idea because it can act as a cradle to hold the fuselage in future assembly steps.

The important thing in the construction of the V-tail is to get the angle right. The hard balsa center strip and the root edges of the stabilizers are all beveled to the correct angle, so assembly is no problem. But trusting the angle to such small levels is not really a good idea, so I made a 35-degree template out of stiff cardboard. I clamped the center strip to the bench and held the template under each stabilizer; this ensured the correct angle for each half. I sealed the joint with thin CA, then reinforced that joint with fiberglass cloth and more CA.

The Elster’s V-tail uses two clever clip-on mounts. This allows you to easily adjust the stabilizer relative to the fuselage. First, screw these mounts to the stabilizer and then clip the whole unit onto the boom. Don’t be misled by the mounting instructions, however. If you install the tail with the clips positioned as they are shown on the drawings, then the control horns-which you will install later-will interfere with the end of the boom.

Do not mount the tail with the boom extending to the elevator hinge line. Instead, mount it so that the boon ends just beyond the aft mounting clip. Once satisfied with the alignment, fix the stabilizer’s position with a few drops of thin CA.

Because the ailerons will be hinged with tape, it’s best to seal the wings with clearcoat, paint, or varnish before you cut the ailerons free. To show off the beauty of the black poplar veneer, I used a clear, water-based Minwax polyacrylic varnish. I applied two very thin coats with a soft cloth and sanded it with 400-grit sandpaper.

The manufacturer was kind enough to draw the outline of the ailerons on the upper surface of the wing, so you need only a very sharp knife blade and and a metal straighedge to cut along the lines. The manufacturer also had the foresight to install a balsa strip inside the wing at the leading edge of the aileron. That means if you cut along the lines, the aileron will already have a balsa face ready for shaping. If you want to be sure, hold the wing up to the light and look through it; you will see the shadow of the balsa.

The aileron servo pockets are also premarked. I he aileron servos will need extension wires al least 20 inches long, and as there is very little room in the wing for connectors, it’s best to hardwire extension rs into the servo leads. A passage for the servo lead is precut, so all you have to do is thread the lead to the wing root. I mounted Cirrus CS- 10 BB servos to the tire upper sheet with GE Silicone It glue.

To mount the wing, I cut two small holes in the top of tile fuselage. I positioned one hole where the servo leads exit the King. The other hole provided access to install the screw plate or the wing bolt. I chose to make two small holes so I wouldn’t compromise the fuselage structure. This is a narrow fuselage, so installing the screw plate requires patience and tiny fingers. I have neither, so I substituted hemostats for the tiny fingers. (I haven’t yet found a substitute for patience.)

Because this is a 2-channel model, radio installation is simple but tight. I used a Hitec Micro 555 receiver with the case removed, a WattAge 150mAh receiver battery and a Hitec micro switch. Even though I chose the Hitec 555 for its small size, I still had to remove the case to adequately fit the receiver inside the fuselage. After some fiddling with the position of the components, I mounted the Cirrus CS-21 BB elevator servo with GE Silicone II.

The only real difficulty I encountered while installing the elevator pushrod was in gluing down the aft end of the housing because it is relatively deep inside the tail boom. I finally drilled a tiny hole in the underside of the boom just ahead of the tail and ran a loop of thread through the hole and around the housing. I then pulled on the thread, which in turn pulled the pushrod housing to the bottom of the boom. It took only a few drops of thin CA through the hole to secure it in place.

After I had installed the radio, I determined that I needed 3/4 ounce of nose weight to get the CG in the recommended range. This was a surprise, as the overall weight is such a factor in hand launching.

On my first day out with the Elster, I logged nearly an hour of “transmitter on” time between numerous launches and landings. When I was nearly finished, I suddenly realized I hadn’t touched the trim settings, yet the Elster had tracked straight and level with my thumb off the stick. I can’t take credit for this level of performance-if truth be told, it doesn’t take a lot of skill to build this plane.

If you’re in the market for a hand– launched glider and want one that’s equally at home on the slope or at the thermal field, you should look into the Elster. You won’t be disappointed.

Cirrus Ventures, 115 Hunter Ave, Fanwood, NJ 07023-1030; (908) 322-7221.

Futaba Corp. ofAmerica exclusively distributed by Great Planes Model Distributors Co., P.O. Box 9021, Champaign, IL 61826; www

Global Hobby Distributors, 18480 Bandilier Cir., Fountain Valley, CA 92728-8610; (714) 964– 0827; fax (714) 962-6452.

Hitec RCD Inc., 12115 Paine St, Poway, CA 92064; (858) 748-6948; fax (858) 748-1767;

WattAge; dist. by Global Hobby Dist

Copyright Air Age Publishing Apr 2001

Provided by ProQuest Information and Learning Company. All rights Reserved