evening gents-
question lets say i see a kit or arf on the net and i am deciding to get it, now we dont all have the exact equipment that it calls for sometimes we put fifferent servos or engines mufflers etc...
but lets say i see one and i would like to buy it. now how do i go to figure the wing loading with the specs given? wing area, wingspan, weight, and what is a good wing loading?
thanks guys-raf

Use this calculator. http://www.csd.net/~cgadd/eflight/calcs_wingload.htm

Check out some of the other calculators there also.

Campy-
i appreciate that calculator thats cool, but how do i figure wing root chord,wing tip chord from the given values? lets say this for arguments sake...
Wingspan 82"
Fuselage Length 55"
Recommended Engine
Size 2c/160
Flying Weight 11.9 lbs - 12.3 lbs
Wing Area 1,007 sq in

All you need is wing area and weight to calculate wing loading:

1007 sq in divided by 144 (one square foot) equals 6.993 sq ft.

11.9 lbs times 16 (ounces in a pound) equals 190.4 ozs.

190.4 divided by 6.993 equals 27.227 ounces per sq ft wing loading.

12.3 x 16 = 196.8 ozs.

196.8 / 6.993 = 28.142 wing loading.

I knew i should have gone to college!!! [:@] Thanks raineday! and im assuming the lower the better correct?!?!

As a general rule of thumb, yes, the lower the better (although there are certain circumstances where pilots actually want higher loadings).


You didn't say what type of plane you want to fly, and that makes a big difference as to what is acceptable in terms of weight.

In basic terms, lowering the wing loading lowers the stall speed of the plane. This means you can fly slower before you get into trouble. A very good thing for newer pilots, especially when practicing landing approaches. However, too little wing loading can result in a model that is difficult to control in windy conditions and can even be hard to land since it floats along forever.

For glow powered high-wing trainers (and I'm sure there are other opinions) somewhere between 12 and 16 ozs of wing loading is typical. For low wing sport designs you usually see loadings between 18 and 24 ozs. Scale models such as warbirds can have wing loadings well over 30 ozs. And they must be flown and landed at higher speeds to avoid stalling.

The larger a model is, the better it seems to handle higher wing loadings. A 1/4 scale model with a 30 oz wing loading will fly fine, whereas a 36" span model that heavy would be a real handful for the average pilot.

Now, these new electric foam and 3D designs are a different ball game. Some of these have wing loadings well under 10 ozs., especially the indoor stuff.

Hi!
Wingloading should be be as low as possible...nothing more to think about than build as light as possible...and that's not always easy...

thanks all, this is very helpful!!! i guess i will begin to practice my basic math skill now, better ge some aspirin first huh?? jajaja thanks all !

Jan makes a good point. When it comes to most kits and arfs, you are limited by the design and materials to just how light you can make them unless you start making modifications to the structure and use lightweight gear. In other words, pay close attention to how much glue, epoxy and extra wood you add when building a kit. It's very easy to overbuild and end up with something a lot heavier than what the manufacturer advertises. I only scratchbuild and build from plans so I have the advantage of being able to select the weight of the wood and other materials I use. If you go with an arf or build a kit as it comes in the box you are limited to fewer areas where you can shave off ounces.

There is a growing trend today to overpower models. If it call for a .46, people will use a .60; if it calls for a .60 people will install a 1.20 and so on. With a few exceptions, this results in heavier models. Eventually you reach a threshold where the power to weight ratio may appear ok, but the airframe/design and flight qualities start to suffer. An eight pound model with a 1.20 sounds good, but not it that model is a 500 sq in plane designed for a .46.

youre right, i tend to stick to the cheper ARFs just because my pockets arent so deep but i would like to build more from now on. as far as overpowering its not really an issue with me but every now and again i see ARFs (cheap ones) and they say something like this and i just wonder about wing loading. oh yeah by the way its for a texan so it would be wing loading for a warbird i guess.

Wingspan 82"
Fuselage Length 55"
Recommended Engine
Size 2c/160
Flying Weight 11.9 lbs - 12.3 lbs
Wing Area 1,007 sq in