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Old Dec 22, 2009, 10:47 AM
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What I have found is a little extra weight does help you when doing certain maneuvers, but at the expense of having a slow floater,.....not to mention down lines! You'll just have to find a happy medium. I have 800ma packs when I want to go slow, then I have 1500ma packs for when it gets a little breezy, or I want to do more pattern type stuff.

Xpress, all of our silos do track extremely well, which leads me to think you may have the wing incidence off by half a degree or so. Would not take much of that or your ailerons not being centered to cause a bad tracking problem. But there are so many variables to cause this type of problem that I could be here all morning writing things for you to check. I'm sure you know most of this already.
If not, there are so very good resources here on Rcg to read .

One thing to check, when installing the wing, I glued the wing to the bottom saddle. there is a little wiggle room there, if you glued middle or top saddle??
Tail is pretty much fool proof. The wings do have a fair amount of washout built into them, which makes them very forgiving in 3D flight. Does yours have washout??
Where is your battery mounted? That has a big effect if it is not mounted as close to center line of wing. I have even contemplated cutting the top of wing inside the fuse to allow me to install the battery "inside" the wing, to achieve Neutral balancing of the plane with battery mounted! So if your Battery is mounted on the side of the fuselage, as with the original factory hatch, when doing KE, it will tend to want to roll inverted! Of course, it will do inverted harriers all day long, pretty much hands free!!

Ok, said nuff, sorry if I got chatty, Vinmech
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Old Dec 22, 2009, 11:24 AM
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Originally Posted by vinmech View Post
Yeah, I think I may have started something at my club! Everyone wants one for X-mas now! Hope Santa has stock in Electrifly! Anyway here is Will flinging his fav plane around again! If this is getting old for you eastern folks, let me know,lol.
Yes, he covered the canopy with black sticky back covering among other things. He has really beefed up his airframe. he has a 450 sized motor in his with 1300 mah batts, the new hitec digital coreless 8 gram servo's (which he says are great!) and so on. Needless to say it has to be heavier than your typical setup!! Enjoy the Vid, I'm sure you'll like it!

http://www.youtube.com/watch?v=e-gVvaEsVfU
When you mentioned that your buddy beefed up his airframe, do you mean he just made it heavier with the heavy setup? Or did he do some reinforcement on certain areas? Or both?
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Old Dec 22, 2009, 11:32 AM
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OK, I see what your saying. One other point is the Skua is $130, so if your flying on a budget that's pretty steep, but I'm sure it's a nice fun plane.
That's the 42" BAF Skua, made of 9mm foam and is supposed to weigh about 2.5lbs and need about 500 watts of juice.

The 33" Skua OTOH is less expensive than the Silo and has Mikes customer service behind it
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Old Dec 22, 2009, 11:34 AM
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Originally Posted by vinmech View Post
What I have found is a little extra weight does help you when doing certain maneuvers, but at the expense of having a slow floater,.....not to mention down lines! You'll just have to find a happy medium. I have 800ma packs when I want to go slow, then I have 1500ma packs for when it gets a little breezy, or I want to do more pattern type stuff.

Xpress, all of our silos do track extremely well, which leads me to think you may have the wing incidence off by half a degree or so. Would not take much of that or your ailerons not being centered to cause a bad tracking problem. But there are so many variables to cause this type of problem that I could be here all morning writing things for you to check. I'm sure you know most of this already.
If not, there are so very good resources here on Rcg to read .

One thing to check, when installing the wing, I glued the wing to the bottom saddle. there is a little wiggle room there, if you glued middle or top saddle??
Tail is pretty much fool proof. The wings do have a fair amount of washout built into them, which makes them very forgiving in 3D flight. Does yours have washout??
Where is your battery mounted? That has a big effect if it is not mounted as close to center line of wing. I have even contemplated cutting the top of wing inside the fuse to allow me to install the battery "inside" the wing, to achieve Neutral balancing of the plane with battery mounted! So if your Battery is mounted on the side of the fuselage, as with the original factory hatch, when doing KE, it will tend to want to roll inverted! Of course, it will do inverted harriers all day long, pretty much hands free!!

Ok, said nuff, sorry if I got chatty, Vinmech
Everything is centered up, even have 0* thrust alignments in the motor (and yes, I tried a couple degrees of thrust alignments too- nothing). My wing is glued to the bottom of the slot at the LE. My plane couples towards the belly, as in it rolls outthat way, indicating where I have my battery is fine (actually ,it probably needsto be higher up in the plane, say in the canopy?).
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Old Dec 22, 2009, 12:10 PM
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Originally Posted by Xpress.. View Post
Everything is centered up, even have 0* thrust alignments in the motor (and yes, I tried a couple degrees of thrust alignments too- nothing). My wing is glued to the bottom of the slot at the LE. My plane couples towards the belly, as in it rolls outthat way, indicating where I have my battery is fine (actually ,it probably needsto be higher up in the plane, say in the canopy?).
Does this mean coupling is cause by not having the weight centered of the axis, moving the battery higher would "axis balance"? I guess I do not have a full understanding of what creates coupling is why I ask.

<gear change>
I know that lateral balance is VERY important to the performance and stability of 3D, I could see that adding additional tracking issues.
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Old Dec 22, 2009, 01:16 PM
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It balances pretty much perfectly laterally, and that's one of the first things I check when an airframe wants to wander about on the roll axis..

I believe my issue with the KE loop coupling is merely just airframe design, rather than the setup. I know of lots of airframes that won't KE loop very well, and will couple out towards the belly.
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Old Dec 22, 2009, 03:36 PM
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Napa, Ca
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From Joedirt,
When you mentioned that your buddy beefed up his airframe, do you mean he just made it heavier with the heavy setup? Or did he do some reinforcement on certain areas? Or both?

JoeDirt,Well,.....both,....he is oversized on his power set-up and he added some balsa bulkheads in the nose, from the wing forward to the motor mount to stiffen it. He said the he could see his nose twisting and tweaking,......he does have way more tourqe than I do. And I am able to punch out really well with mine

From Xpress,
Everything is centered up, even have 0* thrust alignments in the motor (and yes, I tried a couple degrees of thrust alignments too- nothing). My wing is glued to the bottom of the slot at the LE. My plane couples towards the belly, as in it rolls outthat way, indicating where I have my battery is fine (actually ,it probably needsto be higher up in the plane, say in the canopy?).

Xpress, When you pull vertical, do you have to correct to keep it vertical, or does it veer right or left or towards you or away from you? Whichever direction your plane goes while vertical, correct for in thrust at motor mount.
Assuming all your trims are neutral on the plane. Don't forget the Aileron Differential, you need it for axial rolls. play with the amount of Diff till it is rolling on a string! I am able to KE with my ailerons centered, just using rudder and throttle to maintain heading! It'll do KE loops all day long!

From Daoldguy,
Does this mean coupling is cause by not having the weight centered of the axis, moving the battery higher would "axis balance"? I guess I do not have a full understanding of what creates coupling is why I ask.

<gear change>
I know that lateral balance is VERY important to the performance and stability of 3D, I could see that adding additional tracking issues.

Daoldguy,
Having your heaviest component (battery) exactly where the X,Y,and Z axis converge for your CG eliminates the influence it would have in the different attitudes your plane may be in at any given time. The coupling characteristics
are directly affected by the layout or design of the plane! The location of wing (low,mid or high) , Elevator (low,mid or high) and Rudder ( tall, short Large or small surface area, and in regards to coupling, location of Rudder)

So the Ideal layout for 3D is midwing, elevator just above the wing line (to stay in clean air and out of turbulent air directly behind the wing) The Rudder should Ideally be mounted on the midline directly behind the wing/thrust line!

Since that would make for an odd looking tail, most will design the TE of rudder to be wider at the bottom and narrower at the top so that rudder can be located mostly topside.

So,.......Hope this helps a little, I don't claim to be an expert, but I did stay at a Holiday Express last night!

Vinmech
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Old Dec 22, 2009, 04:45 PM
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Originally Posted by vinmech View Post
Xpress, When you pull vertical, do you have to correct to keep it vertical, or does it veer right or left or towards you or away from you? Whichever direction your plane goes while vertical, correct for in thrust at motor mount.
Assuming all your trims are neutral on the plane. Don't forget the Aileron Differential, you need it for axial rolls. play with the amount of Diff till it is rolling on a string! I am able to KE with my ailerons centered, just using rudder and throttle to maintain heading! It'll do KE loops all day long!
Nope, it tracks straight on the verticals, and has perfectly axial rolls (thanks to my inflight trimming ).

I've been setting up foamies for 3 years, I do know what i'm doing

No odd pitch coupling inverted, no real coupling on level KE, very odd rolling harriers, hovers fine, torque rolls perfectly, does 4, and 8 point rolls perfectly, holds a perfect 45* line, both upright and inverted, has axial rolls, doesnt do KE loops without coupling, ect. ect. I've setup everything
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Old Dec 22, 2009, 05:04 PM
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Originally Posted by Xpress.. View Post
Nope, it tracks straight on the verticals, and has perfectly axial rolls (thanks to my inflight trimming ).

I've been setting up foamies for 3 years, I do know what i'm doing

No odd pitch coupling inverted, no real coupling on level KE, very odd rolling harriers, hovers fine, torque rolls perfectly, does 4, and 8 point rolls perfectly, holds a perfect 45* line, both upright and inverted, has axial rolls, doesnt do KE loops without coupling, ect. ect. I've setup everything
Ya Know the tail is really flimsy, Maybe another piece of carbon fiber for the rudder and elevator to stiffen it (prevent it from twisting) would help? Can't think of what else it could be, save for the pilot!
It is different, I can agree with you there. Every plane has its quirks, can't do anything about it sometimes.

Vinmech
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Old Dec 22, 2009, 05:21 PM
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Ya Know the tail is really flimsy, Maybe another piece of carbon fiber for the rudder and elevator to stiffen it (prevent it from twisting) would help? Can't think of what else it could be, save for the pilot!
It is different, I can agree with you there. Every plane has its quirks, can't do anything about it sometimes.

Vinmech
I think it might just be my wing. It's rather flimsy, but it does appear to be straight. I might put on a strip of CF to the TE of the rudder, and likely the LE of the horizontal stab, but that's it (because im running out of 3mm cf ).
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Old Dec 22, 2009, 05:26 PM
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Originally Posted by Xpress.. View Post
I think it might just be my wing. It's rather flimsy, but it does appear to be straight. I might put on a strip of CF to the TE of the rudder, and likely the LE of the horizontal stab, but that's it (because im running out of 3mm cf ).
I would try the rudder first, seems to be the only thing that would affect a KE loop? Would also explain your "Odd rolling harriers" possibly. Keep us posted.

Thanks, Vinmech

ps, If the front of the fuse was flexing like my buddies, that would cause same weird things! maybe stiffen it up as well?
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Old Dec 22, 2009, 06:26 PM
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Originally Posted by vinmech View Post
Daoldguy,
Having your heaviest component (battery) exactly where the X,Y,and Z axis converge for your CG eliminates the influence it would have in the different attitudes your plane may be in at any given time. The coupling characteristics
are directly affected by the layout or design of the plane! The location of wing (low,mid or high) , Elevator (low,mid or high) and Rudder ( tall, short Large or small surface area, and in regards to coupling, location of Rudder)
Vinmech
I am with the XYZ for the purpose of being central on access with out and issue. I was just trying to figure out if the offset of the battery higher, as Xpress mentioned, had some effect on coupling. It would seem odd to me to make it top heavy and away from axial to correct coupling.

While I understand none of us are Boeing Designers, <maybe there are> and we are talking about the Silo and its coupling that Xpress is seeing <try a Holiday Inn Xpress?> can we look at this just a tad farther?

Vinmech, how would you apply your view of coupling to the attached picture? I like what you were saying, sometimes visual aids are helpful.

This is the Infineon i3D, it is my grab and go scratch build, I can fly it is a 10 foot square, hovers nice, 12 ounces. It has a known coupling to the gear, no matter who has built one, what types of foam used, or how well balanced or not. Just for reference, it is 35"ws, 37 inch from spinner to tail, top and bottom wings are twins.

Thoughts, anyone?
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Old Dec 22, 2009, 06:29 PM
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Originally Posted by vinmech View Post
I would try the rudder first, seems to be the only thing that would affect a KE loop? Would also explain your "Odd rolling harriers" possibly. Keep us posted.

Thanks, Vinmech
There was talk early in the thread about the Rudder warping, mine was.

http://www.rcgroups.com/forums/attac...mentid=2833508

So I attached a CF Strip to the bottom to take the bow out of it. This was during the build so I never flew it like this.

http://www.rcgroups.com/forums/attac...mentid=2833668
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Old Dec 22, 2009, 08:20 PM
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Originally Posted by daoldguy View Post
I am with the XYZ for the purpose of being central on access with out and issue. I was just trying to figure out if the offset of the battery higher, as Xpress mentioned, had some effect on coupling. It would seem odd to me to make it top heavy and away from axial to correct coupling.

While I understand none of us are Boeing Designers, <maybe there are> and we are talking about the Silo and its coupling that Xpress is seeing <try a Holiday Inn Xpress?> can we look at this just a tad farther?

Vinmech, how would you apply your view of coupling to the attached picture? I like what you were saying, sometimes visual aids are helpful.

This is the Infineon i3D, it is my grab and go scratch build, I can fly it is a 10 foot square, hovers nice, 12 ounces. It has a known coupling to the gear, no matter who has built one, what types of foam used, or how well balanced or not. Just for reference, it is 35"ws, 37 inch from spinner to tail, top and bottom wings are twins.

Thoughts, anyone?
Bipes add another dimension to the whole scenario!! lol

That is a sweet design by the way. So I assume your saying it pulls to the gear in KE? Well,.....does it do the same when KE on either side in straight line? So you must apply "up" elevator to maintain straight line?
Do you know what your thrust angles are? Both wings are dead parallel to each other? And they are both inline with Stab, Incidence wise? Wingtip to stab distance are equal on both sides? Cabanes are perpendicular to wing, or angled? Do both wings have ailerons or just one? There are just so many variables here as you can see, most people just mix it out and live with it!! But just the same, answer me these ?'s and I'll think on it.

By the way, if your like most and like to 3D, you'll be a little tail heavy, which would cause some people to trim elevator slightly down. Which would cause your problem, but I think you know about that. But I gotta throw that out there for the nubes

Thanks, Vinmech
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Old Dec 22, 2009, 08:42 PM
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Originally Posted by vinmech View Post
Bipes add another dimension to the whole scenario!! lol

That is a sweet design by the way. So I assume your saying it pulls to the gear in KE? Well,.....does it do the same when KE on either side in straight line? So you must apply "up" elevator to maintain straight line?
Do you know what your thrust angles are? Both wings are dead parallel to each other? And they are both inline with Stab, Incidence wise? Wingtip to stab distance are equal on both sides? Cabanes are perpendicular to wing, or angled? Do both wings have ailerons or just one? There are just so many variables here as you can see, most people just mix it out and live with it!! But just the same, answer me these ?'s and I'll think on it.

By the way, if your like most and like to 3D, you'll be a little tail heavy, which would cause some people to trim elevator slightly down. Which would cause your problem, but I think you know about that. But I gotta throw that out there for the nubes

Thanks, Vinmech
I have built several of these and thrust angles are all 0 to the thrust line, wings are evenly spaced from the thrust line, H Stab in on thrust line, cabane/wing struts are squared to the wings, wing struts lean forward as the top wing is a tad forward. 35inch WS, 37 inch from spinner to tail. Ailerons on both wings, single servo with the V shaped 3D servo arm to keep the motion linear.

It will always go to the gear no matter if it is a knife edge loop, or just a knife edge. The thing that makes this plane what it is, is the fact it is very well mannered, even better for the nubes, but still is strong for 3D.

Here is a video of the Maiden in the dome, this was the 2 flight, I handed it off to a great pilot who have never flown this plane before. He does a couple KE loops, and if you watch the bottom side of the loop, it is trying to level the wings.

http://www.rcgroups.com/forums/showp...7&postcount=19

I dont fly her to tail heavy, different packs give different trim since the lipo is right behind the motor, Bipes are typically tail heavy to begin with.

Excuse the off topic guys, little R&D to understand 3D flying and construction <yes, cheezy disclaimer>

Thanks
Ron
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