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Old Jan 02, 2010, 04:00 PM
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BillHones's Avatar
Sussex, NJ
Joined Oct 2009
152 Posts
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Originally Posted by JMartin06 View Post
Just received my first Alula for Christmas! I'd planned to use a 72MHz radio to fly it, but was suprised with the DX5e as a gift. I'm very new to RC, would love to run my Alula with this 2.4 GHz system, but suspect it's missing critical components (e.g., adjusting throws, deflections). Can anyone tell me if and how I can use the DX5e to fly the Alula? Thanks

sell the dx5e on ebay or on rcgroups and buy a dx6i. i sold my dx6 on ebay and bought a dx6i for only 17 bucks more!!!
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Old Jan 02, 2010, 04:42 PM
Steve Chamberlin
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Bay Area, CA
Joined Oct 2009
121 Posts
maiden flight

I took my Alula for its maiden flight today. It was a very disappointing day, but that's mostly my fault. Before leaving for the field, I carefully balanced the plane at the dimples, and set the control throw distances per the manual for "beginner". I faced into the wind (probably 5-10 mph), gave it a medium-strength overhand toss, and... whunk! Straight into the ground, hard, about 3 feet in front of me. So I dialed in a little up elevator trim, tried again, and whunk again. Dialed in even more up elevator trim, tossed it again, and it pitched straight up, stalled, flipped 180 and smashed nose-first for a third time. None of these "flights" went more than 5 feet.

I finally had a sort-of-successful toss by just releasing the Alula over my head, giving only the slighted forward push. After more throws and lots more hard ground-slamming, I decided that what I thought was a level overhand toss was in fact angled downward. Making a point to toss slightly upward seemed to help some.

At this point, after maybe 10 minutes, I noticed a crack starting to form between the pod and the body. Foolishly, I put a piece of Blenderm tape over it and kept going. The grass was wet with dew, and the tape didn't adhere well. In fact, the Blenderm already around the belly skid and wing edges was starting to peel off due to the moisture.

Eventually I pushed my luck to try some gentle side-arm launches, which were more successful. I probably got the plane 15-20 feet up, with a minimum of bonk-on-launch. Unfortunately the flight characteristics seemed pretty bad. It would typically climb up at a 30 angle or so, then stall and go into a dive straight down. A couple of times I did manage slow and level descent lasting maybe 10 seconds, but I found the plane to be very tippy and difficult to keep level.

The stall behavior of the Alula seems very unforgiving, compared to what I'm used to with my Slow Stick. The stall comes on abruptly, and in the blink of an eye it goes from level to pointing *straight down*. I did a lot of stalling and bonking the ground, or stalling, diving, and overcorrecting straight into another stall. Overall the plane seemed very twitchy compared to what I'm used to with the Slow Stick.

Eventually I gave up and came home, with my muddy, cracked, tippy Alula. Do I just need more practice? Might the CG be off? Should I reduce the control throw distances below the "beginner" ones from the manual that I'm using now?
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Old Jan 02, 2010, 04:45 PM
Practice Makes Precision
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United States, MO, Knob Noster
Joined Jun 2006
3,531 Posts
What was your AUW? Sounds like it's pretty heavy, and just falling rather than flying.
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Old Jan 02, 2010, 05:03 PM
Gravity sucks
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United States, WA, Richland
Joined Mar 2006
2,499 Posts
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Originally Posted by schamberlin View Post
Eventually I gave up and came home, with my muddy, cracked, tippy Alula. Do I just need more practice? Might the CG be off? Should I reduce the control throw distances below the "beginner" ones from the manual that I'm using now?
It sounds like your CG is off and the extra reflex you have dialed in is killing your lift. The CG on this bird can be very touchy. I like mine at the aft end of the dimples rather than in the center. And you must balance it on sharp points, like pencils to make sure you have it right.

Mike
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Old Jan 02, 2010, 05:52 PM
Erk
All thumbs, no scents
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Vallejo CA
Joined Nov 2005
597 Posts
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Originally Posted by schamberlin View Post
Eventually I gave up and came home, with my muddy, cracked, tippy Alula. Do I just need more practice? Might the CG be off? Should I reduce the control throw distances below the "beginner" ones from the manual that I'm using now?
Sounds just like my early experiences with the original Alula.

Cg is fairly critical on all flying wings - definitely the first thing to check. The PITA of this is that too far forward and too far aft can both exhibit the lack of control you're experiencing.

Servos need to center precisely, too -- if not, all kinds of unpredictable behaviors result. Test this on the bench; support the bird on blocks or books, and measure the surface heights on both wings. Waggle the sticks, remeasure. If they aren't in same places before and after, it's possible your servos aren't precise enough for the Alula. For testing new servos, secure long sticks (about 12" is fine) to the horns, and repeat the measuring process before you install them. The extra length will reveal any deviations in centering or end-point resolution. You need two servos that center the same and travel the same amount for any given stick position -- without that, the Alula will be difficult.

Same-same for binding of control surfaces -- these need to be smooth and as slop free as you can get them. I don't know what pushrods come with these, but they need to be pretty stiff -- the surfaces are large enough to cause flex in unsupported rods. In mine, 2mm CF rod was on the edge of too much flex so I added wire loop guides in the middle, which helped a lot.

Reducing throws might help. Changing the mechanics of the linkage for maximum resolution can do wonders without sacrificing authority, though -- outer hole on the servo arm and inner hole on the control horn (I think I've got that right) is the most accurate translation of stick position to surface position. If you've got it the wrong way around, you get fewer steps between full deflections, and hence less accurate control. A sixtyfourth inch one way or the other is a LOT.

Dual rates if you have them -- serious plus. If not, try to get used to very small stick movements. VERY small.

Alula threads worth reading:

http://www.rcgroups.com/forums/showt...ighlight=alula

http://www.rcgroups.com/forums/showt...ighlight=alula

Yes, it's a lot of reading. Sorry!

All that said, if you're in the SF Bay area, you're in a hotbed of DLG flying. http://www.bayrc.com/ has some extremely friendly and very experienced pilots; if they're having a DLG clinic, try to get there early.

If you're up North, drop me a PM and I'll do everything I can to get you flying.

I know it's a lot of 411... and I hope it helps. This hobby is too much fun to give up out of frustration!
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Old Jan 02, 2010, 07:01 PM
Steve Chamberlin
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Bay Area, CA
Joined Oct 2009
121 Posts
Don't worry, I'm not giving up, but I am frustrated. I'll check the CG again, and maybe reduce the control throws a little. I'm currently at +/- 4mm for elevator and +/- 9mm for ailerons, which is what's recommended for beginners in the manual.

AUW is 177 grams (6.25 ounces). That's after buying little 0.25 ounce lead weights, sawing them into quarter sections, and placing them as far forward in the battery compartment as possible. I have no idea how people are getting sub-6 ounce weights. I'm using the stock BlueBird servos and receiver battery.

I live on the peninsula south of San Francisco. There's a DLG pilot who's often at the park where I fly, but he wasn't out today. I'll definitely seek his help, next time I see him.

Here's a photo of my cracked pod. Looking at the underside, the crack starts at the corner where the pod and fuse meet, and extends diagonally backwards into the receiver compartment. The crack also penetrates all the way through to the top side. If I flex the pod very slightly, I can open about a 1mm gap in the crack, so getting glue in there may be tricky.

What's the best way to repair this crack? CA? Gorilla Glue? Packing tape?
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Old Jan 02, 2010, 07:44 PM
Steve Chamberlin
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Bay Area, CA
Joined Oct 2009
121 Posts
Update:

Plane balances perfectly at the center of the dimples.

Repaired the crack with fiber strapping tape, since there's really no way to get glue deep into the crack.
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Old Jan 02, 2010, 10:07 PM
And Repairs
TyFlies's Avatar
Grapevine, TX
Joined Jan 2009
262 Posts
Quote:
Originally Posted by schamberlin View Post
I'm having trouble getting the recommended control throw distances with my new DX6i transmitter and new Alula. I can't get the elevons to move far enough, even after "exercising" the hell out of them to make sure they're loose.

I'm using the stock Blue Bird servos, with push-rod in the middle hole on the servo horn. Turned on elevon mixing, set dual-rates to the recommended 20% for elevator and 60% for aileron, and left all other trim/travel settings at defaults. That setup gives about 1.5mm deflection in each direction for elevator, and 4mm for aileron. The manual recommends 4mm elevator and 9mm aileron for beginners, so it's way too short.

Attempt number two, I moved the push-rod to the outermost hole on the servo horn, set travel adjust to 120% in both directions for both servos, then set dual-rates at 50% for elevator and 100% for ailerons. That setup gives about 4mm deflection in each direction for elevator, and 8mm for aileron. So it's almost there, but I have no where else to go to get more travel. I'm maxed out, yet the manual suggests 6mm elevator and 14mm aileron for advanced pilots, so it must be possible.

Can anyone help? Thanks!

Edit: Will it damage the servos to set the travel adjust to 125%? Why is 100% not the maximum travel? On a powered plane, if my throttle travel adjust is "only" at 100%, will I not get max power at full throttle?
I'm new to the Alula - in fact mine hasn't shipped yet -- but I've got 3 elevon flying wings set up on the dx6i. The dx6i has a programming issue with elevons. My wings flew OK, but not great until I set things up according to the work-around which is on this link...
http://www.rcgroups.com/forums/showthread.php?t=940867
I hope this helps.
Ty
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Last edited by TyFlies; Jan 02, 2010 at 10:15 PM.
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Old Jan 03, 2010, 01:45 AM
Throw it like you hate it
RCPC's Avatar
United States, CA, Castro Valley
Joined Apr 2007
3,079 Posts
Quote:
Originally Posted by schamberlin View Post
Don't worry, I'm not giving up, but I am frustrated. I'll check the CG again, and maybe reduce the control throws a little. I'm currently at +/- 4mm for elevator and +/- 9mm for ailerons, which is what's recommended for beginners in the manual.

AUW is 177 grams (6.25 ounces). That's after buying little 0.25 ounce lead weights, sawing them into quarter sections, and placing them as far forward in the battery compartment as possible. I have no idea how people are getting sub-6 ounce weights. I'm using the stock BlueBird servos and receiver battery.

I live on the peninsula south of San Francisco. There's a DLG pilot who's often at the park where I fly, but he wasn't out today. I'll definitely seek his help, next time I see him.

Here's a photo of my cracked pod. Looking at the underside, the crack starts at the corner where the pod and fuse meet, and extends diagonally backwards into the receiver compartment. The crack also penetrates all the way through to the top side. If I flex the pod very slightly, I can open about a 1mm gap in the crack, so getting glue in there may be tricky.

What's the best way to repair this crack? CA? Gorilla Glue? Packing tape?
some thin CA will wick very well into the cracks. i suggest you make a slit on both sides of the fuse about 1 inch back of the tip of the pod all the way to about an inch aft of the pod/wing joint. in this slit, place a small carbon rod, maybe an 0.050" diameter, and then run some thin CA in the slit to fix the carbon rods. the pod is inherently weak and needs extra beefing to take the abuse we give these gliders. i wish you luck in getting you alula working. flying wings are very sensitive to CG location... and so are gliders. when you have both working against you, trimming becomes VERY important. just take your time. add expo to your controls if you have the ability. start with about 50% or so. i am sure you will have it flying well soon. fly it on grass for the first few times to any crashes will yield minimal damage. good luck!
cheers
paul
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Old Jan 03, 2010, 11:53 AM
Steve Chamberlin
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Bay Area, CA
Joined Oct 2009
121 Posts
Alula paint job

Here's a photo of my Alula cleaned up and decorated, before I smash it up again. I shamelessly copied the design from the one Teezer posted a few weeks ago. The birds at the park will be running scared!
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Old Jan 03, 2010, 12:02 PM
Registered User
Corona, CA
Joined Sep 2007
923 Posts
I crashed my Alula last weekend...because I forgot to turn the Rx on, lol. Anyway, there was a crack on the fuse, which I fixed with some laminating epoxy. I just put on glue on the joint, then just flex it open and closed over and over, and the glue will work itself deep into the crack.
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Old Jan 03, 2010, 12:19 PM
Throw it like you hate it
RCPC's Avatar
United States, CA, Castro Valley
Joined Apr 2007
3,079 Posts
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Originally Posted by Mr._Mulligan View Post
I crashed my Alula last weekend...because I forgot to turn the Rx on, lol.
sorry to hear this. glad you got it fixed. post your experience here: http://www.rcgroups.com/forums/showthread.php?t=1166805
cheers
paul
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Old Jan 03, 2010, 01:36 PM
Erk
All thumbs, no scents
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Vallejo CA
Joined Nov 2005
597 Posts
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Originally Posted by RCPC View Post
some thin CA will wick very well into the cracks. i suggest you make a slit on both sides of the fuse about 1 inch back of the tip of the pod all the way to about an inch aft of the pod/wing joint. in this slit, place a small carbon rod, maybe an 0.050" diameter, and then run some thin CA in the slit to fix the carbon rods. the pod is inherently weak and needs extra beefing to take the abuse we give these gliders.
That's an excellent point, to which I'd like to add -- since you need weight to balance, why not make it functional? And since the pod on these is a little weak, why not make that functional weight in the form of reinforcement, like CF uniweb or tow, applied with CA? _The_ trick on the old Alula was thinned Goop over the whole pod... solved the shredded pod issue but didn't add much stiffness.

I don't know if Tap Plastics still carries it, but the last 1" by 3" hunk I bought about 4 years ago has saved my donkey too many times to count. IIRC it cost less than $10. It might be a little harder to find than tows, but it's a lot neater to work with. It has just enough binder that you can pull out strips about 1/8" wide, leaving the web behind-- with some careful knife work, you can work it into your feathers design.

Nice paint!!

Oh, I just remembered something; for me, running the plane up to flying speed instead of tossing it helped get those first trim flights done without all the breakage. Not as much, anyway. HTH!
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Old Jan 03, 2010, 01:51 PM
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Corona, CA
Joined Sep 2007
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Originally Posted by RCPC View Post
sorry to hear this. glad you got it fixed. post your experience here: http://www.rcgroups.com/forums/showthread.php?t=1166805
cheers
paul
I voted. It was the first time...and hopefully the last.
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Old Jan 03, 2010, 05:04 PM
Steve Chamberlin
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Bay Area, CA
Joined Oct 2009
121 Posts
Thanks for the advice everybody. I took the Alula out again today, and had a bit more success. After a lot of fiddling with the radio, I finally got a few easy hand launches to coast smoothly down into the grass. Then I took it up a small hill, and tried a bit of slope soaring. There was maybe 5 mph of wind, and a better pilot could probably have done well, but my longest flight at the slope was 38 seconds. I did manage to catch the plane once, and hit myself with it unintentionally twice. Ouch! The rest were all belly landings in the grass (or nose landings!)

This is my second plane, after two months learning to fly on a Slow Stick, and I'm finding the Alula difficult to control. If I take the SS up high and then cut the motor, it glides sedately and predictably. When it stalls, it just noses down a little and picks up speed again. In comparison, the Alula feels very twitchy in the air. At the slope, it seemed to change direction nearly instantly and sometimes unpredictably (wind gust?). Stalling the Alula is like dropping off a cliff: it rotates 90 degrees down like it's on a hinge, and plummets. It also moves fast, much faster than I'm used to making low-altitude maneuvers with the SS, so my brain needs to work faster.

Is this how the Alula is supposed to behave? I'm not sure if I simply need to practice more, or if my plane is out of adjustment. I met up with the DLG pilot at the park, who looked over the plane and made sure nothing was grossly wrong, so I think the setup is pretty good.

Unfortunately the Alula suffered some major damage at the end of the day. The pod broke completely off. I've repaired it with Gorilla Glue, and will get some CF rods to reinforce it. (By the way, what is CF tow and uniweb?)

Also, there seems to be something wrong with both my servos now. They are the stock Blue Bird servos from Dream Flight. At full up/down elevator (about 2mm movement), one of the servos buzzes as long as I hold it there. The other servo kind of stutters and skips back and forth as it moves, but it eventually ends up at the right position. Lastly, the servos now seem to move at different rates, so when I apply up elevator, one elevon reaches its position before the other. Is this a symptom of stripped gears? Both servos were behaving fine this morning before I took the Alula out to the park.
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