Eggcellent Contest

[Gigatron]

Make a big ol’ parachute out of paper (use Davinci’s design, he probably knew what he was talking about) and encase the egg in tape like a dang mummy. If it’s wrapped so tight that the shell can’t shift, it can’t break.

-Fred

[Anonymous]

You are on the right track, at my school the students also have a target area. The closer to the target the more points they get. So you might want ot re-think the glider idea. A large paracute seems to be the method of choice of most students.

Good Luck! Bob

[Matt90]

I did this assignment in my physics class back in college days too… You might want to re-read the specifics of the directions - paper only. Some profs will look at cardboard and/or wax paper as “not paper”.

Glider ideas are ok but they can tend to run into walls or lose lift under the wings. You want something that doesn’t fly too long as it may cost you points. Plus, double/triple wings and cardboard tubes at mass - and you need to disipate your kinetic energy at impact.

That being said…I would suggest you take a good look at the engineering that went into landing some of the probes on Mars (pathfinder, sojourner, etc). Tiny, fragile hi-tech devices that had to land safely in an atmosphere 1/1000th the thickness our own. hint hint [:D]

-Ro (an astrophysicist at large)

My teacher is cool with it, I asked him if I could build a glider out of cardboard and he said “OK, as long as it doesn’t hit my car.”

I’m still toying with the design a bit, looks like the wings will be two layers for 4 feet then the outer panels will only be one layer thick, so they can be more readily bent upwards. Mass is a big worry right now, but I could always make the wings longer, or thinner.

We will get bonus points for the length of time the egg spends in the air, so that’s OK.

Stinks we can’t have airbags like on the Mars Rovers :). That would have been too easy.

[Matt90]

I build RC airplanes, so if you are going to try that approach, allow
me give you some tips based on my hard-learned lessons. Time to
dig out your propellor hats!

(1) Wingloading = Aircraft Weight / Wing area
If you want your aircraft to fly well enough that it will land
the egg intact, you should probably shoot for a wingloading of
0.05 oz / sq in. This may be more difficult than you initally
expect, given the significant weight of an egg.

(2) Center of Gravity
Most aircraft have the center of gravity approximately 1/3 of
the distance back from the wing leading edge. Test and adjust
as necessary to obtain the desired glide path. Don’t assume that
a pitch-up / pitch down tendency can simply be fixed by adjusting
the elevators. A proper CG is crucial.

(3) Airfoil
Research the effects of different airfoils. For example, a highly-
cambered airfoil will provide excellent lift but high drag. This is a
handy tool for evaluating airfoils.
http://www.grc.nasa.gov/WWW/K-12/airplane/foil2.htm

Personally, I think that a glider is going to be one of the most complex,
time-consuming, and yet one of the most-common solutions to the
problem at hand. Since you mentioned that originality earns points,
I myself would try a more straight-forward approach (or downward, perhaps).
I would try to slow the egg’s fall with something like a balloon, or maybe
even something that auto-rotates, like a maple seed:

Of course, building model airplanes is a wonderful pursuit that I greatly enjoy.
I don’t mean to turn you off of them in anyway.

Thank you for the tips, they are helping me out, especially the airfoil computer.

I was looking into the autorotation idea, perhaps a simple helicopter toy design with a bumper at the bottom would work well. That’s definitely my alternate plan.

I’m not going to lie, as soon as I heard about the project I figured it would be an excuse to build a massive glider. [:)]

[Matt90]

Yes, pics, please! (It’s a model, right?)

The bend in the wings is for lateral stability. Couldn’t hurt.

I also think that a spiral glidepath may be a good idea. It would be a good way to bleed off speed and keep the glider “under control” and not fly off into the next county… of course, then you gotta make sure it doesn’t hit the building…

Also, the shallower the glidpath, the better. That way the downward speed is tranferred to forward speed- the shallower the glide, the “slower” the egg will fall. But if most of your speed is forward, then you run into issues on landing, i.e., a high landing speed. THAT’S why I thought some type of skids may be a good idea.

Wow. I’m I having too much fun with this? [;)]

Spiral seems to be the way to go, still need to work on that idea though.

Glide distance won’t be a problem, there’s a very large, open parking lot in front of the stadium.

Way too much fun!

[Jim_Barton]

I “solved” that puzzle/assignment 30 years ago by dropping the egg by itself from a seventh story window. Yes, it went splat. Yes it DID fall FIVE stories without breaking. Howler by all, teacher not amused! I said I DID follow instructions. I cant believe they still give that as an assignment! Pointless really…

[(-D][(-D][#toast] I love it!

I guess that would be known as “following the letter of the instructions but not their spirit.”[:D]