interested

[Guest RussianRoulette]

oh man, i just lost my entire post which i was typing! Argh. Il paraphrase. I am 15 yaers old and have an itch (a passion really) to do some sort of project in the field of aerospace or mechanical engineering. I like a challenge and am not afraid of something which might be alittle over my head (to a certain extent lol) and have a willingness to learn. Any suggestions which you could give me would be greatly apreciated. Also, suggestions as to what i should be learning now (cad etc) and literature which i shoudl read would be greatly apreciated. Thanks!

[BPHgravity]

Build a machine that produces more energy than it consumes.

[Cap'n Refsmmat]

Build a pulsjet powered airplane.

http://www.aardvark.co.nz/pjet/

[Guest RussianRoulette]

I was being serious. Im glad you guys were 2.

[BPHgravity]

I am being serious. The accomplishment would be brillant and fantastic. You could change the world.

 

Since you didn't like my first suggestion, I feel I should come up with another to make up for it. How about you re-invent the wheel, or maybe build a better mouse trap?

 

I think alternative energy is the next big thing, kind of is now. There is alot of energy on this planet we aren't using. Dinosaur fuels need to go.

[Guest RussianRoulette]

Im looking for something that i could do, that i could study and work on. Wing shapes vs efficiency etc. I dont know how i would go about testing something like this however. Ideas please?

[Dave]

Try something in the field of model rocketry (a topic that I've become very interested in recently). It's challenging, especially trying to keep the rocket stable during flight.

[YT2095]

a rocket assisted glider is a project I`ve been thinking about for a while now. a bit like these UAVs that use a rocket to get them off the ground, except this wouldn`t have any more power after that and simply just glide. I`de be interested to see something like that in action! it seems every design I make has some critical flaw in it, primarily the initial burst of thrust, either makes it loop round and crash or the wings buckle. it`s a really nasty project!

[Dave]

Getting stability on those things must be a complete nightmare.

[atinymonkey]

I have a rocket assisted model glider in my loft. Well, most of the remaining big bits are in the loft, providing proof of the instability. You can control a glider at speed, but just don't try and turn sharply.

[Dave]

There's quite a few R/C controlled rocket gliders on the market as well nowadays, which are quite funky.

[Phi for All]

a rocket assisted glider is a project I`ve been thinking about for a while now. it seems every design I make has some critical flaw in it, primarily the initial burst of thrust, either makes it loop round and crash or the wings buckle.

Is your trajectory vertical like a rocket or are you starting at an angle as a plane would?

[Dave]

I guess vertical and as the altitude increases, pitch over to allow for the wings to take effect on landing. They're quite good fun to fly (apparently), and you can get kits to build them. I think there's a kit space shuttle glider you can get for a relatively small amount somewhere.

[Phi for All]

I guess vertical and as the altitude increases, pitch over to allow for the wings to take effect on landing. They're quite good fun to fly (apparently), and you can get kits to build them. I think there's a kit space shuttle glider you can get for a relatively small amount somewhere.

RussianRoulette, this sounds like the perfect thing for you to get involved in. When YT2095 posted regarding buckling wings I immediately thought of ways to decrease stress during initial thrust, and your mention of wing shape efficiency earlier fits in perfectly (I love designing paper airplanes and always dreamed of being able to launch them from as high a point as possible). CAD would be great to know unless you're really good with sketch, also 3-D modeling, any computer skills would help. And get on good terms with your shop teachers, of course.

[YT2095]

Is your trajectory vertical like a rocket or are you starting at an angle as a plane would?

a very gentle angle, like a plane. the idea started when one of my rocket cars actualy lifted off the road by about 3 foot, it was a gentle lift too, so I thought I`de try and improve upon it, I haven`t managed it yet

[Guest fulcrum]

Here's something that I did with a friend when I was 15. I made my first cambered paper chuck glider and have made several hundred of them since. Im actually rather crazy abt them. These arent like your run-of-the-mill flat winged things: they have camber on the wing, and a barrel for the body, and are crafted from paper and paper glue... I have made ones with swept wings, straight wings, forward swept wings, tailless planes, flying wings... and I remember Suze (my friend) made one which looked exactly like a BAC Lightning and that thing flew marvellously...and I remember one of mine which looked so much like an F-104, with a very thing flattish wing...I had to use slats on that thing to improve lift!

 

We've made a few with air ducts and vectored the thrust out in a directionwith a paper cone out the back of the "barrel", usually with a nose inatke, like a MiG-15 or 17. I had a few of these gliders with floating canards and spring loaded and damped canards so they'd generate the same lift coeff at different alphas for the plane as a whole. So when you throw it up and it goes into a climb (and these things can reach 40 ft+...electric pole heights) the canard levels it out in the climb and when it loses its momentum at height, it tends to do tailslides!! Great fun... But the flying wings so far have been devious - can never get them right 100%...

 

You can get lift hysteris (lift coefficient varies non-linearly with angle of attack) on these things by experimenting with a strake in front of the wing. You can get it to generate a vortex and if its stable and doesnt detach with different alphas (if you get really lucky) you can get it to do a very very short radius loop or a spiral turn!!!

 

Try something like that...you'll always enjoy doing something thats simple/easy to make and whicxh is complex in function. Thats because you get to learn a lot by experimenting with these things. Btw if you can get these right (since they truly represent the four forces as it is done on conventional aircraft) you will get a good idea of the kinematics, trims and such on aircraft as such so the idea doesnt end with the paper

 

Im trying to take a pic of these and post a scanned image...maye I;ll do that in another post to give u an idea.

 

On to other ideas - ever considered putting bird flight into motion on these things - maybe a paper flapping wing airplane.... Its a bloody business with the twisting wing and the stress calculations but its bound to be interesting. Hmm...havent thought abt that so much...any other ideas?

[Wolverine]

Get going on Navier-Stokes, you solve that in closed form and I can guarentee you that you'll be a legend

 

No seriously, model rocketry as already stated is a very good way to get into the business of aerodynamics, control, propulsion etc. Water rockets are generally a gr8 place to start off.

 

The Wolverine

[dryan]

Roulette:

Does your school have a Science Olympiad team? That'd be a great place to start; try Bottle Rocket, Tower, Trebuchet ("Storm the Castle"), and Robot ("Robot Ramble").

 

That 'a way, you can compete with others your age.

http://soinc.org/ for more information - (somewhat out-of-date until new rules are released in September.)