|
|
|
|
||
|
D/FW
Joined Aug 2004
685 Posts
|
Quote:
|
|
|
||
|
|
||
|
|
Quote:
|
|
|
||
|
|
||
|
|
Quote:
<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. |
|
|
Latest blog entry: Weak Signals Toledo 2012
|
||
|
|
|
|
|
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. |
|
|
|
|
|
|
|
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 |
|
|
|
|
||
|
|
Quote:
).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
|
|
|
||
|
|
||
|
|
Quote:
![]() It is different, I can agree with you there. Every plane has its quirks, can't do anything about it sometimes. Vinmech |
|
|
||
|
|
||
|
|
Quote:
).
|
|
|
||
|
|
||
|
|
Quote:
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? |
|
|
||
|
|
||
|
|
Quote:
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? |
|
|
Latest blog entry: Weak Signals Toledo 2012
|
||
|
|
||
|
|
Quote:
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 |
|
|
Latest blog entry: Weak Signals Toledo 2012
|
||
|
|
||
|
|
Quote:
lolThat 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 |
|
|
||
|
|
||
|
|
Quote:
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 |
|
|
Latest blog entry: Weak Signals Toledo 2012
|
||
|
| Thread Tools | |
Similar Threads
|
||||
| Thread | Thread Starter | Forum | Replies | Last Post |
| New Product **NEW** Great Planes ElectriFly Riot 3D EP ARF | Mandy | 3D Flying | 259 | Jul 06, 2012 03:44 PM |
| New Product Electrifly E-performance Series Extra 330s 3d Ep Arf | Jim T. Graham | Product Announcements | 2 | Jan 24, 2009 01:59 PM |
| New Product **NEW** Electrifly Riot 3D EP ARF | Mandy | Product Announcements | 0 | Aug 07, 2006 12:46 PM |
| New Product **NEW** Electrifly Reactor 3D EP ARF | Mandy | Product Announcements | 0 | Aug 07, 2006 11:37 AM |