My Wooden Airplane
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12/7/2009 - 12/15/2009

Wing Rib Reinforcement

Based on what I learned from my first attempt, even though I tested each piece of wood before building any ribs with it, I decided to test the completed ribs. I held each one in the middle and gave it a good wiggle. Not too surprisingly, some wiggled more than others,
but a couple actually broke. I realize that this is probably more stress than the ribs would ever encounter in flight, but after fixing the broken ribs, I decided to add some reinforcement to
the areas that looked weak to me. (Weak because of wood selection, not because of any
design flaws.) The result is a set of ribs that, I'm sure, are heavier than originally intended,
but at least now I have some peace of mind that they shouldn't break later on.

Let's see. Original gross weight of 1200 lbs, designed for a maximum of 6 G's is 7200 lbs.
Divide that by 30 ribs and you get 240 lbs per rib. Each rib is approximately 60 inches long,
so that means every inch of each rib needs to support about 4 lbs. (I know it's not evenly distributed like that, but these are just rough calculations.) Still, I don't think these ribs
will have any problems supporting that kind of weight.

Total Time: 24.5 hrs.