Revisiting an old friend/challenge

So when I was a young engineering student, in my first aerospace class, I was given the task of working with a team to build a small propeller driven airplane out of balsa wood. I had three other team-members, one of which was my roommate, James, and we decided to split into two teams in order to build two planes, the better of which would become our entry.

So my roommate and I worked hard at designing our little plane (not really) and eventually started cutting our airfoils out of balsa wood. After hours of painstaking cutting and gluing, we discovered that this wasn't really working out (we were also covering the frame of our airfoil with saran wrap, which was not the greatest idea). So, we hit upon the idea of solid wood wings. Yeah, that's about as good an idea it sounds. James and I tried a few tests on the ground, which didn't work, so I figured that if we had a little more time in the air to gain lift, it might work out. So I took it to the third floor of the building, wound up the propeller, and let her fly. And she dropped like a rock. Then came the competition, and that's exactly what happened. My roommate went on to be a political science major, and given how four years of aerospace treated me, he might have had the right idea.

So now, having graduated with a degree in aerospace engineering, I am returning to the challenge that bested me all those years ago. I will build a functional balsa wood propeller driven airplane! Or die trying. Well, probably less 'die' and more 'be ashamed'.

So, I went out and bought some balsa wood, tissue paper, glue, and an exacto knife. I sketched out a basic design, with two rear horizontal stabilizers and a fin, plus, a flat, angled wing strategically located at the center of mass of the the rest of the plane. And, of course, a propeller up front.

Construction went easily enough, despite my lack of a ruler. I just built a basic frame for the wing, and reinforced the joints to keep it sticking together, and took a length of balsa wood and glued together the fin and stabilizers.


Then came the affixing of the tissue paper, which was fun, it worked out pretty well. Smear glue, attach tissue paper. Done. Then I attached the wing! Which was a bad idea, as I didn't have the propeller, and couldn't actually put the wing at around the center of mass. So I guessed.


Then I went out and tried to buy a propeller, for which I actually had to buy a kit balsa wood plane, which I felt somehow defeated the point of building my own. So, I got home and attached the propeller!


So, now comes the flight test. Joy and excitement! So, that center of mass thing is actually pretty important, because any lift the wing got caused it to pull up until it lost lift, and then fall backwards to the ground. So I put some weight on the nose and put the wing at a higher angle to generate more lift. The result? Well, it's just about the same.



In a good headwind, it'll still fly somewhat, but not fantastically. So we're gonna call this a beta product for now. I probably should have done some math with this, just to get myself halfway right, but I cracked open my old aerodynamics textbook and promptly remembered why the midterm left me a sobbing mess behind the computer science building. Next week, something a little more domestic, I think.