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Old 01-28-2013 | 08:14 AM
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JohnBuckner
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From: Kingman, AZ
Default RE: how much is too heavy?

OK great Chad I will go over how easy it is to find a wing loading. That wing loading is of course your guide as to what to expect from your airplane. It does of course require a judgement call on your part as to what is going to an easy flying slow trainer like airplane or perhaps a hot rod. That will come with experiance as your progress and learn. This is why many manufacturers but not all do list their projected wing loading right on the box. Something that was almost never done in the past but it is such a useful tool more and more customers are demanding it.

Looks like Sensei ran his own numbers for you and there you go but I am going to walk you through the simple steps its easy to remember and do anytime quickly

You need the wingspan in inchs and this is tip to tip including through the fuselage area. You will need the average wing chord if any tapers or elipses are involved use the chord measured at half way from the fuselage to the wing tip. And you need the total weight ready to fly but without fuel measured in ounces.

As you already know its then simple with this info to multiply the span by that average chord to arrive at the wing area and expressed in square inchs.

Now we can get to the 'rest of the story'

Divide this total Wing Area (in square inchs) that you have already arrived at by 144 (this number never changes and is what you use each time) The result will be the Wing Area in square feet.

Now that we have the Wing Area expressed in Square feet and we have the Total Weight expressed in ounces the last step is easy: simply divide the Total Weight by the Wing Area and the result will be that magic number that is quite a useful tool.

Get into the habit of computing the wing loading of all your airplanes and you will soon have surprisingly accurate benchmarks for your own prediction.

John