ST Models' ASW28 revisited. - RC Groups
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Sep 04, 2012, 06:52 PM
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ST Models' ASW28 revisited.

Hi, guys.

I've finally got my Specter dialed in enough that I felt like a change of pace and resurrected the ASW. Following studioRS's lead I added dihedral and he's right. It absolutely is the best and most important mod one can make to this plane with the possible exception of improving aileron throw. It flies better and looks spectacular. It's a nice little flier for a 2meter scale foamy.

I've also added a Dynam motor and 25A ESC to fly with 3 cells. The motor is a bit of a dog, about 100watts with a 10X6" prop, but it does climb better than the stock 2 cell setup. Now..?

I'm still not satisfied with the aileron or spoileron throw so I'm going to fix it as soon as I pick up some balsa trailing edge stock. I'm going to increase the length of the ailerons by around 6 inches and I'm going to scrap the whole stock aileron setup in favor of servos mounted out on the wing for direct actuation of said ailerons. All I want is to be able to do slow, scale, rolls and get better glide path control. Aside from the aileron/servo mods I'm also going to cover the bottom of the wings with Skyloft (a thin Nylon fabric). This should make up for cutting servo pockets and maybe add enough stiffness to further accentuate the aileron control. I'll post pictures when I get into the "rebuild".
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Sep 05, 2012, 10:56 AM
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Glad I could help with some inspiration. Although, I can't take credit for the dihedral mod, that goes to HunnerBunner.

Yes, simply LOVE the way my ASW-28 sails now. Of course I've got a more modded motor and 8x4.5 Graupner prop which just about takes it vert if needed.

I'm thinking of sheeting my wings with balsa rather than the cloth, they flex a lot in 10-16 mph head winds. I just use MIX1 45% rudder with ailerons on my DX6i, seems to glide well, still need to coordinate the left thumb on rudder too. Next big upgrade for me is the new Graupner mx-12 HOTT radio. Variometer, GPS, and ear bud voice telemetry. Plus it has two 3-position switches.

Yeah, rolls are definitely not happening with the stock ASW-28 servo setup. Looking forward to your wing mods.
Sep 07, 2012, 12:37 PM
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My aileron stock came in and I'm just about to rip the old ailerons off. I also received a couple 950mah, 3 cell, batteries that are quite impressive. That's nearly 2 ounces less battery plus I should be able to pull the tail weight I added for the 1300mah batteries. I'm hopeful that I'll make up for the smaller capacity with a quicker climb and better soaring. Now? Time to rip some foam and sand some balsa!
Sep 07, 2012, 04:59 PM
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Phase one complete.

I've got the bigger ailerons rough shaped and the holes to match. Alas; it started raining so I'll have to wait to sand and finish them but now I can go out for a few beers!. I also checked out the new batteries and, for some reason, they give me about 150 more RPM. Since my motor is a bit pathetic that's a pretty significant difference and, at least for the first climb with a fresh battery, should provide a noticeable difference.
Sep 10, 2012, 04:18 PM
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Installation complete.

I've got the new ailerons all hooked up but haven't had good flying weather to try them in the air. The pics are self explanatory and I'll worry about cosmetics after I'm sure the installation did what I hoped for.
Sep 10, 2012, 04:21 PM
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Looks good Peter, you have some serious aileron travel there! Rolls shouldn't be an issue now.
Sep 10, 2012, 04:26 PM
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That's actually full "spoileron", sRS. It's available if I need it for ailerons but I'll start with about half of that. It will be much more sensitive around neutral no matter what since the only flex now is the entire wing. Not the ailerons or linkages!
Sep 13, 2012, 01:24 PM
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I finally got out to fly with the new ailerons and smaller batteries and the improvement is all I had hoped. The roll is still a bit sluggish but it will roll. I suspect that the wing is flexing a bit when I get her fast enough for a roll but I'm still undecided about whether to "glass" the wings since it thermals a lot better with the reduced weight. Despite the heavier wood ailerons I still managed to take off about 35 grams. Now? I need a little more motor for low inverted flight!
Sep 17, 2012, 08:40 AM
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That's awesome! Yeah, wing wobble is going to get sorted on mine. Absolutely love this sailplane, I'm going to say it...

More than my trusty Radian. Yes, it is a far superior sailpane for indicating thermal lift and staying in thermals, plus the added benefit of being a scale ASW-28

Flying my ASW-28 yesterday, on my second battery pack, I was getting crazy thermal lift!

Conditions: Essex, VT RC field butts up to acres of corn fields. Absolutely sunny, 62 deg, clear, zero clouds, winds were light WNW at 6mph and the hawks and buzzards were catching huge lift.

There was a buzzard way out over Rt. 128 and I pointed over there. Shut the motor off and followed his circles - WOW ballooned right up and at one point I must have gained at least 400ft. Most of that flight was motor off. Thermals travel downwind, so had to keep in that one or grab another.

This sailplane indicates thermals differently than my Radian, better in that it doesn't wag the tail or rock the wings, it just goes UP and penetrates the wind forward at the same time. Think it goes up more than forward! I can scoot in and out of a thermal faster (better motor and more control) and fly smoother than a R/E only sailplane. Plus, this sailplane has the added benefit of just looking like a scale ASW-28 and oh so Kewl with the howling swooshes on fly-bys.

Need to program spoilerons, slowing it down on landings is next. I don't know how many motor off, right on the deck passes I made before I had a slow enough landing.

I currently have a DX6i and one of the MIX1 is used for aileron > 45% rudder. I do not use the Y-plug and have each servo plugged into its own port on the AR600 Rx. Is there a way to program spoilerons on the DX6i ?
Last edited by studioRS; Sep 17, 2012 at 10:14 AM. Reason: oops!, it is an AR600
Sep 17, 2012, 10:05 AM
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Found this for flaperons DX6i, seems like it will work. It might work for spoilerons if I reversed percentages? I'll try it today.

I don't want to get to carried away with this... I'll be upgrading to the new Graupner HOTT mx-12 radio system anyway. One of the things I need is telemetry, so I can see what my battery level is after being stuck in a thermal for 20 min! They also have an audible earpod variometer adaptor, is that schweet or what !?!

AXN Floater Jet / Clouds Fly flaperons with DX6i (6 min 16 sec)
Last edited by studioRS; Sep 17, 2012 at 10:19 AM.
Sep 17, 2012, 10:17 AM
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I don't have a DX6i, or any other Spektrum radio, but I have seen references to setting them up for spoilerons. Spoilers helped a bit with the original linkages but now I can almost parachute the ASW down with any head wind at all. I have also found that adding just barely enough throttle to kick the prop blades out makes for a very effective speed brake but then one can induce a tip stall.

You're right. The ASW is surprisingly good at exploiting thermals. In fact, though I would like to get a bigger scale sailplane, I'm afraid it won't thermal as well as my favorite bit of foam! My best flights have been where there's a little wind and I use the thermals like dynamic lift. I don't try to stay inside the thermal but fly in an egg shaped ellipse with the narrow end inside the thermal and at nearly stall speed. Then I let the nose drop and the speed rise during the wider, down wind, portion of the pattern.

The field where I do most of my flying is downright unfair. I have big stretches of asphalt on three sides so, with any wind at all from one of those sides, I get monster lift right over said field. Cool days with bright sun are the best and I'm actually looking forward to winter flying. My guess is that sunny winter days, after a little snow cover, will provide very good thermal conditions.
Sep 22, 2012, 01:32 AM
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Shot some photos the other day after catching the epic thermals. I was there by myself, so couldn't take aerial shots. LOVE this sailplane.
Sep 22, 2012, 02:19 AM
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I love it a lot too.

The mix I use on my 9x is "flaperons" with negative throw. It's a guessing game of aileron and flap/spoiler throws and then I still had to adjust the pushrods. It's far too complicated for me to explain further and probably wouldn't have any value for a Spektrum.

I bought a new motor for another project that, despite getting pretty hot, survived pumping 350 watts at 33.3 amps into a 10X4.7 prop. Since I need to flight test it anyway I'm going to bolt it on the ASW with a 9X5 prop. With said prop it dropped down to 23 amps and 265watts and 10,700RPM! It also runs nice and cool. I figure I'll never run that motor for more than 10 seconds like my Specter 1800.

Since I'll only need brief bursts of power I figure I can probably still get 40 minutes or more with my nice, light, 950mah batteries. 54grams makes a noticeable difference on the tip stall.

Mine is very much a prototype at this stage. I'll either pretty it up over the winter or get another one and start from scratch.

And, just to be clear, the very first thing a person should do to this model is scrap the ailerons and their linkage. Replace them with stiff ailerons, whether you stiffen the foam or replace them with wood, and replace the hinges. Move the servos out on the wing and use pushrods and control horns.

I got over 40 minutes of flight time today with numerous climbs, spent much of the flight doing aerobatics, and came down with my 950mah battery still at 11.7volts. And I haven't mounted the new motor yet!

My Specter is a little better in some categories but I do, indeed, love this plane. What it lacks in performance it makes up in looks and sound.
Sep 24, 2012, 10:23 AM
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I think that I'm going to perform your aileron mod and move the servos out. I will also add carbon tow strips to the top and undersides to help stiffen the wings. I'm going to skip sheeting with balsa and instead just cover with Econocoat, lower temp covering after the mods. The stock aileron contraption is hideous looking and not that effective too as you mention.

I was out flying yesterday and like a knucklehead, tried launching on about 1/4 power. Well of course it just went 20 ft and dropped. Nosed in without much carnage and only popped the front tab on the canopy off. Hmm, ok lets put some tape on the front and back and go soaring again. Winds were 6 with13mph gusts from the W, landing strip runs N-S. Ridge / slope soaring over the corn field back and forth.

This next launch was better and on a dive the canopy with ultra scale pilot flutters off about 600+ feet up right over the corn field - like a Bermuda Triangle - nobody gets their planes or parts back...

There were four of us and we took off into the corn maze with a canopy search party. Just while we were standing around talking about never finding it, one of the guys hold it up! Success! Wahoo! I'm going to order a spare from Towerhobbies just in case.

Ok, well that was fun, let's go for more soaring. Swapped batteries, taped up the canopy again on all four sides and was enjoying back and forth staying up into the wind. When it came time to land, I couldn't for the life of me get it to come down. FULL down elevator provided ZERO effects. WTHeck? Anyway, decided to lightly apply some throttle to open the blades, this helped drop the nose and come down safely. Checked out the elevator and the connecton on the servo control wire was loose! Servo works fine, wire slipped on connection = zero elevator. Learned my lesson, always double check flight controls prior to takoff even after a successful flight.
Sep 24, 2012, 02:05 PM
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I think you'll like it. Best to get the sanding, and there's lots of sanding, out of the way before winter sets in. I was going to stiffen the wings but, at least with my current motor, I don't think it's necessary. Just taping on the stiffer ailerons and making sure the inboard end overlaps the main spar stiffened them up quite a bit.

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