Spring Time Fun

So school has been out for over a month now, and what do I have to show for it? Well, apart from several adventures that Tess has already chronicled for our faithful reader(s?), I have mostly been working on small overdue projects at work.* I have also becoming more and more invlolved in an engineering project here at BYU. We are building a solar airplane, and I am on the team that is designing the wings. I am sure that I will post more about this in the future.

One thing that I haven't talked about from school is that in order to participate in this project, I had to take a class in airplane fundamentals, where, as part of the coursework, a partner and I built a model plane from a kit. We used this model in several tests that we did to learn more about aerodynamics, structures, and propulsion. The final for the class was taking our plane out to point of the mountin and throwing it off: if it flew, we got an A, if not, well, we failed.

Here is a photo of the building process, it came with these paper plans and a stack of wood. This is our assembled wing and fusalage and tale sections before we covered them (the orange plasticy stuff in the bottom left).

my partner and I with the assembled plane

just minutes before launch, possibly the last time the plane is fully intact

This is a video of our first launch. That is our professor throwing it, with one of the TA's at the controls. It took a while to get used to flying it before I could fly it on my own. The TA would stand right next to me and grab the controls out from my hands before I wrecked it. The first time I only controlled it for a few seconds, but after a little while I could fly it for as long as I wanted with little help.

It is kind of intresting how it works, The plane has no engine at all; it relies on the winds to push it forward and keep it aloft. It has little electric motors on it that are hooked to a radio to control the elevator and rudder. We didn't even wreck it, though the two other teams that built planes did wreck theirs--one catastrophically, tearing apart his wing and damaging his fusalage, which is kinda sad since it took each team about 80 man hours to build and he only flew it for about 10 minutes.

From building it, I learned a lot about aircraft. Here is an interesting piece of information. Notice that the wings are not straight as one might expect, they curve up towards the ends. This is called dihedral (well "polyhedral" really, but it's the same idea). This gives the plane the ability to self correct if it rolls to the right or to the left much like a marble will have the tendency to roll to the bottom of a circular bowl when pushed up one of the sides. It is one of the things that makes the plane inherently stable and good for someone just learning how to fly (like me). At any time if you just let go of the controls, it will straighten and level out and just glide along. It is really interesting how it works (interesting if you like engineering, I guess) since no motors are used. It all works becouse of the shape of the wings and tail and position of the center of gravity.

Anyhow, you could stay up on top of that point all morning and fly for as long as you wanted, flying out over the valley, back into the updraft next to the point to regain altitude, and then back over the valley again. It was really fun.

Tess even flew for a while (this shot looks posed, but I promise it's not, she really was flying at the time) and clearly enjoyed it despite the wind.

In any event, it was really fun, stay tuned for more news.

*For those really intrested, fire up your iphone or other mobile browser and head on over to mimobile.byu.edu as an example of a small overdue project I have been working on.