Heavier weight might help because it has greater inertia. But for vertical performance, you want the plane to be lighter. For windy condtions, an aerodynamically streamlined airplane is better than a heavy plane.

This is a simple solution if you have the money and have room in the engine compartment. Install a heavier powerplant or change out your flight pack to one with larger cells (sub C). The increased weight of the flight pack mounted to the firewall will effectively move the CG forward. The last thing you want is dead weight. I realize there are times when dead weight is all that can be added but look for ways around this. I have an ESM Hawker Hurricane that took 1.5lb of weight in the nose to balance. I swapped out the installed Saito 1.8FS and replaced it with a Saito 2.2FS and removed 17 oz of dead weight.

Of course folks have moved the battery in front of the firewall. Where are ya when we need ya John (Buckner)? An appropriately strengthened structure is needed for both the battery pack and the foam isolating material. The ones shared are adjacent to the engine extending forward from the firewall next to the motor mount. Ya better have a lot of extra room for that approach. Need to keep the glow goo away if glow powered.

A true 0-0-0 plane balanced and trimmed properly will handle turbulence better than just adding weight to a plane. The problem is there are very few planes that meet this criteria. Almost all trainers, sport, and scale aircraft are far from that design and will be more stable with a higher wing loading, to a point. You will loose some top end speed, have a higher stall speed, and loose a some agility, but depending on the airfoil and the amount of weight this can be very subtle, especially with the more modern airfoils. If this is to be used for sport aerobatic flying then that small amount of weight will have little to no noticable effect. I personally would not go to extreme effort to shave that little bit of weight. If you are building a competition A/C then weight should be considered throughout the build.

No matter how streamlined a plane is a lighter wing loading will be more affected by turbulence then a higher wing loading.

Pardon the dumb question - what is a 0-0-0 plane?

A plane set-up with 0 wing incidence, 0 stab incidence and zero engine offsets (down-up, right-left)....

A 0-0-0 airplane such as the one is question (fully symmetrical foils I think) can't be trimmed to fly all attitudes without mixing some electronic mixes.

A heavier wing loading does not improve any plane's (model and full scale) handling in wind or otherwise. A heavier plane simply flies... well, heavier, more sluggish to respond to commands. If you think you like flying a heavier plane, find a friend with the same plane that is 1 pound lighter and take a few flights in all conditions. You will change your opinion. I partially disagree with the guy who said it's only a 5% increase so you won't feel it. A noob probably will not. The focus of the noob is to keep the crate flying. A seasoned pilot will feel the difference

What Speedracer said holds. Try to move everything you can forward and add weight ONLY as last resort

Cheers and....

I'm glad I'm not the only one who understands basic aerodynamics. I received a bunch of negative critizism when I talked about wing loading and how it applies to our models. It appeared to me there are a whole bunch of pilots waiting for an accident to occur due to their lack of knowledge.

Some of us know that we don't know - but - because we don't know it's a real "beach" trying to figure out what question to ask. And, being an intermediate flier - we wouldn't know if a plane is doing this or that. Arggg - this hobby has sooooo many layers - that's why it's so cool ...

An aerodynamically streamlined airplane may fly faster or may need less thrust for a given speed but it has nothing to do with its response to turbulent atmosphere.

The turbulence action is to affect the momentary angle of attack varying the lift and the drag.
A heavier machine will not be affected as much due to its higher inertia.

It will need less control action from the pilot and so is easier to fly.

We have to differentiate between the two main types of pilots.
Those who fly by constantly correcting what the model does and those who tell the model what they want it to do. In the first type mentioned the correction will be slower with a heavier machine (every thing else being identical). The second type of pilot mentioned will anticipate what they want and control the model accordingly.

Ask yourself ___what type of pilot are you?

If you are constantly moving the transmitter sticks, just tearing holes in the sky then it is not likely to make much difference what the model wing loading is. It might not even be important that the model is balanced or not as long as you have more thrust then weight and huge control surface areas.

I recently was watching a fellow flying and his pattern was straight up, reverse to a dive fly the bottomof a U and straight up again. He kept doing that for about 5 minutes. I then noticed that his buddy landed the plane.

In such flying conditions, who cares about wing loading or balanced model?

I am getting out of this discussion.I have nothing more to contribute than what I already said.

Cheers,

Zor

I built a metal strap to hold receiver batteries on firewall just for that purpose! That will help to keep from adding weight. I put the foam wrapped battery in a plastic bag to help keep oil off.

I would just add the 6 ounces and fly it. Then start removing weight to get the CG to YOUR liking. Most manufactuers' CG locations seem to be on the nose heavy side. I like a plane what I consider to be really neutral- not nose heavy, not tail heavy. I find this by test flying and by either moving things around if possible or by adding weight (which nobody likes to do, but is neccesary sometimes). Don't be afraid to experiment with the CG. Just be sure to start a little nose heavy first, otherwise you might not even get a chance to experiment.

You can apply aerodynamic theory and rhetoric all day long, but the bottom line is, how do YOU like the way your plane flies?

Case in point: I have built about six Ultra Sports since the early 90's. The plane is designed to have cap strips over the ribs. I have built the wing in the following configurations:

Cap Strips
Fully sheeted
Sheeted top, Cap Strips on bottom

And I built one "Lite" version where I went through painstaking measures to build it as light as possible.

The results: I like the way the fully-sheeted wing flew the best. I liked the "Lite" version the least (in fact, I gave the plane away after two flights)

Personally, I don't think it's worth it to move the engine. Won't make enough difference anyway but, I doubt you would even notice the difference in the way it would fly with the 6 oz. added.

Anyway, I'm pretty sure they grounded the space shuttle so all the rest of the science that's been kicked around doesn't add up to much of anything in this particular case.

Just my .01

With all due respect there MN, you only had 2 flights on it. IMO it was no where near being trimmed correctly and you made a rash decision. Had you hung onto it and took the time to correctly trim it you may have kept it. I have been competitivly flying aerobatics for almost 15 years and it takes me about 50 flights to get an airplane dialed in. Not because I am slow at it, to do it correctly thats just how long it takes on average.

With all due respect, I know when a plane doesn't act the way I like it to act. The plane was trimmed just fine. I just didn't care for the "feel" of the lighter version.

When flying full scale I love a light snappy A/C, however when I am flying full IMC with passengers it is far more comfotable for them and far easier for me if I am closer to the max gross weight. There is less reaction of the plane to turbulence giving a smoother ride and requiring less frequent corrections. As Zor said it depends on the pilot and how they want their plane to fly. Speed you obviously want to wrest every ounce of performance from your plane, have the skill and don't mind needing to fly it every second. some prefer a more relaxed form of flying and are content with a heavier, often more nose heavy, model. What most are saying is unless you want to eke out that last ounce of performance, or are already overweight, don't worry about a little extra weight.

The OP's airplane has a plug in wing. Should just move the tube and mounting hardware back, problem solved.

I like my airplanes light. I like them with low polar moments. Since I build most of them, I have more options available to me than people that assemble ARF's. This allows balancing the wing by sorting ribs, and the rest of the wood by weight. The equipment (engine, servos, batteries) are all picked with the idea of minimum weight with the require performance. Even the spinner selection is usually limited to Tru-turn, because the engines just run better with them, and they are light weight.

I agree with Shawn, that it takes about 50 flights to really dial in most models, but it is totally unnecessary for many model pilots because they just don't have a feel for it, and quite frankly never will. You can get about 90% in about 5 flights, but you never get 100%. Sometimes the deck is just stacked against you, and it' so subtle that you never know why. I've seen too often that a slight problem in shaping the leading edge of the wing manifests itself as an airplane that will never trim out or have that solid feeling.

I think I'd have just bolted a bunch of weight at the C/G after having put so much time into building it if I thought too light was the problem.

I've found that putting existing designs on radical diet plans can cause unwanted structural flexing unless the whole structure is reconsidered. This is particularly true when plastic coverings are used on open frame construction. What might feel fairly stiff on the ground doesn't stay that way with flight loads.

Indeed. Its a very iterative process with all the interactions. Its easy in the heat of the moment to get tricked into treating symptoms rather than diseases too, and that sends you down a rabbit hole of 10 wasted flights.

So a correctly trimmed 2 pound electric park flyer will fly well in a 15 knot wind? I don't think so.

Do you people not think? Weight is not his problem, balance is. Adding a pound of lead at the CG won't do a damn thing for him. He either needs to remove some weight in the tail or add some weight in the nose. The battery under the engine mount trick seems like a good idea. Or, and this is rather radical, tear the covering off the tail feathers and remove some weight there.

One big problem is getting theenvironmentalists up in arms about using lead as a weight, if you can even find it.

Hello HighPlains,

As I wrote earlier, I am not discussing weight and the resulting wing loading anymore.
The consensus of experienced fliers is well evident in the last few postings.

Whatever you imply as "polar moments"

Balancing the wing? ___by sorting ribs? ___You lost me. I have to catch up with you .

Yes agreed; no doubt the engine knows the brand and characteristics of the spinner .

With our short flying season here, 50 flights is nearly half our season capability.
Perhaps I am one of those that "never will" . I will guess that I might not need 50 or more flights but rather 50 or more years. I am there already (going on 57 years now 1955 to 2012).

And all this time I understood that the atmosphere separation takes place some distance ahead of the leading edge and the actual shape of that leading edge in not really important. One thing I can say is that my foam Radian pro has many dents on its wing leading edges and I do not notice any difference in its flying. Probably a good indication that I am "one of those that frankly never will ".

It does not prevent me from having lots of enjoyment building and flying my models.
I prefer flying my Super Skybolt because it has a high wing loading and defy turbulence and gusts.

Cheers,

Zor

Finding lead is easy.

http://www.rotometals.com/Lead-Sheet-s/31.htm

A quick recap - There are two separate discussions going on, so reading comprehension is required.

1.) On the issue of an airplane being "two light", add weight and get back to us.

2.) Moving the wing back on the fuselage will balance the plane. Easy to do when it has a wing tube and simple mounting.

We return you back to your regular programming.

Zor,

Two objects can weigh the same, but the force it takes to accelerate them to the same angular rotation varies based on the distribution of the weight. Think dumbbell, with the weight on the end vs same weight concentrated at the center. Low polar moment, though I guess being from Canada Polar might have a different meaning.

Sorting ribs by weight puts the heavier ribs in the center of the wing if constant chord, but even when tapered, you can balance a wing with careful selection of which panel each pair of ribs go to. Same with all the other pieces that go in the wing.

Dirty Harry said it best - "a man's gotta know his limits"

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So a correctly trimmed 2 pound electric park flyer will fly well in a 15 knot wind? I don't think so.
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At first I read this and thought what an over exaggerated example it is. But I thought about it more and the answer is a yes! A well set up and trimmed 2 lb airplane would fly better then a poorly set up and trimmed 2.5 lb airplane in a 15 knot wind. Again, the airplane sees wind as a change in airspeed. A poorly setup airplane will react to changes in airspeed so obviously it will react to wind. Ask yourself if your airplane's trim changes at all between 1/4 and full throttle. If the answer is yes then it is not trimmed correctly. Does it really matter? Not if you are happy with the overall performance.