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Discussion Starter · #1 ·
How do you Blance 3D planes, and is it easyer to fly them nose heavy or tail heavy the first time? I have never flown profile's befor Just wanting to be careful so at least the first flight goes good! :wink:
Any hints or tips in the world of 3Ding?
Thanks Brian
 

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Start with the CG in the reccomended range and fly the plane. See how it feels. Flying at 50-60% power nice and level, roll inverted and see how much down elevator it takes to hold level flight. Now start moving the CG back a little at a time (a Great Planes CG machine comes in very handy).

As you move it back the plane will become more elevator sensitive and more aerobatic. Keep repeating the inverted flight check as above. When you reach the point where the plane flies essentially the same, inverted or upright, you should have a very aerobatic plane on your hands.

Warning, once you reach the point where the planes flies 'hands off' inverted (requiring no down elevator), moving the CG any further back needs to be done with great care and consideration. You are entering the zone where extreme aerobatic ability can turn into plain old instability and an almost unflyable plane.

So far, I think when you hit that inverted vs upright balance point you are good to go.
 

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I'd allmost agree with Jim, except I like to use a LITTLE down while inverted. (very little, like just leaning on the stick) This is probably just personal taste, but I really don't like the totally nuetral setting. I don't ever use my CG machine anymore. Just get it a bit behind recomenmded (Or where it looks right) and fly. Move the battery back or add temporary tail weight 'til it's great!!

Other notes: Bill and I have been playing CG games a lot, and nose heavy seems a lot worse on profiles than in the old sport planes. Bill and I have both had our Sledges nose heavy at some point and they just fall out of the sky! Yesterday I switched from an APC prop and extra lock nut (because the prop is so thin) to a wood prop and no extra nut. Probably lost just an ounce, but I could really tell.
 

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Discussion Starter · #4 ·
So when I hit that inverted vs upright balance point that "Jim D" was talking about, the plane will hover, right?!
And anyone have the Magnum .46 BB ABC Engine i have it order from towerhobbies should be here tomarrow, how dose it compair to other engines in the same class?
Thanks allot for the responce guys!,
Brian
 

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Planes balanced the way Jim described are easier, IMHO, to hover than a nose heavy one. They pretty much do everything better as far as aerobatics goes. You just have to watch for elevator stalls at slow speeds.

I like a hands off plane upright or inverted, but a hair of down pressure for inverted doesn't bother me at all. As long as I'm not holding 1/4 stick to keep inverted flight, I'm OK, pending it does other things well.

Just be careful not to convince yourself that the plane does the hovering. The pilot still does tons of work to keep the nose up on the small profiles. Some planes and set ups are better than others, but none are easy, until practice prevails.

As for the Magnum, some of the older Magnums had carb trouble. The newer designs are much better. Power is pretty much in line with the non-hot rod engines of same size. For example, it will probably not out pull an OS 46 AX or a Webra 50, but it will probably desimate an Evolution 46 or anything with LA in the name. If you fly it for a while and decide you need more power, the exhaust port should be similar to other engines and you can look into a tuned exhaust for it.

Good luck!
 

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TailTwister said:
I like a hands off plane upright or inverted, but a hair of down pressure for inverted doesn't bother me at all. As long as I'm not holding 1/4 stick to keep inverted flight, I'm OK, pending it does other things well.

Just be careful not to convince yourself that the plane does the hovering. The pilot still does tons of work to keep the nose up on the small profiles. Some planes and set ups are better than others, but none are easy, until practice prevails.
Twister is tellin it like it is here. I like mine balanced equal, but as he said, if it just requires a rouch of down while inverted that's no big deal either.

But the real truth is the part about the pilot. Yes, having the right equipment set up properly will go a long way towards 'enabling' you to hover and fly 3D, but there is no magic solution. Nothing but stick time and lots of burned fuel will get you there. I have only recently gotten the hang of some of this 3D stuff. Hovering at eye level is still an excercise that requires ALL my attention and rattles my nerves, I need lots of practice. But get a capable setup and go burn fuel, lots of it. You will get there.

Now I have to get the nerve to bring that high alpha knife edge down lower :shock: Practice... Practice....
 

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Discussion Starter · #7 ·
I have the power-line Eagle and i finished puting it together and the plane is so tail heavy that when i put my fingers on the main spar the tail hits the ground! Should i balance the plane right side up or up side down? I did it both ways and the tail still drops. I know that i did not do anything wrong when i was puting the plane to gether because the plane is a ARF, and i have the bigest engine recommended for the plane (Magnum .46BB).
I try to fly the plane like this because it was a ARF and i could not belive that the plane could be that far off so i thought that maybe it should be like that (ive never had one of these profile 3Ds before)and that was a big mistake, it did not hurt the plane very much but needless to say it does not fly very well like this.
I tryed puting a ton of the stick on weights on the front of the plane but i did not have enough to even change the balance at all, this cant be right? What am i doing wrong? I really need some advice im really wanting to fly!!! :D
Thanks,
Brian
 

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We'll at least need a picture Brian. I've never seen one of these. More info on gear, total plane weight, etc. would help.
 

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Discussion Starter · #9 ·
The box says the plane weight is 3.3lbs and the engine weight is 1lbs.
Lenght- 47in
Wing Span- 44.5in
Wing area- 697.5 sq. in
Radio- 4 channel 5 servo
Engine- Magnum XLS .46 BB ABC 2Cycle
The plane is a ARF 8oz. fuel tank
Propeller size- 10*6
Brand new, never been wrecked.
I will try to send a pic. but if not there is a pic. under general chat were we are now, then go down to the topic that is titled "powerline 3-D profile plane" by Bryguy
If you need more info please wright back and tell me what you need.
Thanks
Bryguy
 

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Discussion Starter · #10 ·
Guys i could really use a little help balance this plane, ive never seen a plane so tail heavy i dont know what to do! Once again the plane was an ARF so i could not have built it wrong. Please if you have any tips at all PLEASE reply.
I mean i could totally weight down the front (ive got two strips of the stick on weights that are 6*1/2*1/8, and that is still not enough, that is alot of weight!!!)and CUT holes in the tail of my ARF but i cant beleive that is what i would have to do, that seems totally unreasonable to me. Has anyone ran in to anything like this before?
Thanks BryGuy, the good Guy :D
 

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Bry, I'm looking into this plane through a local hobby shop that almost got into selling them. The guy here said the guy selling them flaked big time.

Seems like you are going on the assumption that you screwed up. Don't bet on it. you can only move so many things. One thing that I don't see you mention is whether you might be able to move the engine forward. That is the big move to balance when the simple stuff doesn't do it.

Are the servos in the tail? If so, you could move them to the wing.

That's all I can think of. Are you near any other Bros that could put eyes on it?

Take some detailed pics and post them here or on the gallery, or email me at [email protected]

I believe we can help you but the plane may not be too great. If you could get your money back based on it being not as advertised, you could get an Extreme Flight for just a little more.
 

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Bryguy, lifting the plane by the spar and trying to judge how much the tail drops doesn't really tell us much since we aren't there. Try moving your fingers back until the plane sits level, then measure the distance from your fingers to the recommended balance point. Just guessing, I'd say you need to get that distance under 1/2" for the first few flights. Also, are you sure that the spar is the recommended balance point? Sometimes it isn't.
Calculating the CG point would not be a bad idea either, mfgr's suggested points can be off for a variety of reasons. Shoot for somewhere in the 28%-35% range.
Where in MO are you?

Gary
 

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Discussion Starter · #13 ·
Sorry guys!!!
I finally got a hold of the phone number for power-line hobbies the place that makes the Eagle, and they said they invertantly left off the last page of the instruction!!! and that last page told were the CG is, a very inportant detail. He said that they would e-mail the last page of the instruction.
How do you like that? Man that makes me mad, I took the plane off the other day, cause i thought that this is how the plane should be, because its a ARF and all, and it did not go over at all, it went up uncontrolably then back down, messed it up a little.

Do you guys think they would refund me any for this mistake that they caused?
But thanks for all the help, I would like to apologize for power-line hobbies.
Bryguy
 
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