Optimal design for a glider

[silverscorpion]

Hi all,
There's a tech fest coming up and one of the events is aero modelling. Here, we've to build a glider out of aluminium or balsa. There'll be a catapult which will be used to launch the glider into air. From then on the glider should glide and cross a specific distance. These are the criteria based on which scoring is made...

The winners will be decided based on the following criteria:

• Time of flight - The glider which is in the air for a longer time gets THROUGH!!!

• Stability of the glider - The glider has to glide and not merely be projected by the catapult.

• Glider design - The participants should explain to the judges, the theoretical feasibility of their design.

There is no engine or motor powering the glider. The only force is that of the catapult. Suggest the optimum design of the glider which stays in the air for a long time. Also should we use some cloth like things to make it like a parachute, so that it stays in the air for a long time. Pls help... Better if some diagrams of the model is present...

Thanx...

[The_Big_K]

Hi SilverScorpion,

Check the following site that has some information about building gliders that will get you started -

http://www.eng.cam.ac.uk/outreach/CU...sign/index.htm

I'm not the right person to talk more about this, but I'm very much interested in aeromodels ! Once your team builds up your glider, do not forget to put our site's name onto it

I'm sure there are aeronautical engineers on CE who might read this thread. Guys, we need your help!

We'll be waiting for the pictures of your glider!

-The Big K-

[kidakaka]

Firstly, have you seen the catapult? Do you access to a similar one to do your test runs on each of your prototypes? If not, then modelling the glider so as to get the best out of your launch would be priority.

What degree would the catapult launch your model? Is it variable? Remember your projectile motion concepts ... for the glider to work, the model must be very robust ... think of a better way to put the model together - cellophane tapes, glue, et al should be avoided. For the model to really glide, your lift under the wings has to be just right, plus having the ailerons (those things at the back) would be a good idea to stabilize the body.

[panchal]

SilverScorpion,
Are there any dimensional limitations for the glider? What are the minimal dimensions required for the glider to fit the catapult?

[einstein89]

hope its unmanned
glider must be extremely light ,
google for standard dimensions tht is length of wing , elevator , etc
just google and find out necessary info
glider being light will keep it in air ,
position of flaps will decide time of flight ,
elevator , rudder etc will decide its direction and height
think about design ,
certainly aerodynamic , google it too
u may find best results if u try urself
we can only suggest
also , wat r the limitations of glider dimensions check tht too

[panchal]

Well, now a days one can get information about almost anything on google, and who doesn't know that. If I read it right in the first post, it's about a tech fest or a competition. So I was wondering if any limitations or restrictions were set by the competition organizers.

[hangwaiter]

hi silver
as i'm mad about flying wings, and a hangglider pilot myself, i would strongly suggest that you opt for a flying wing concept, as you have to accommodate a huge speed range: the cat is going to zip the model into the air at a speed where a high lift wing section and profile would generate enormous drag. on the other hand, once you go into glide, you may wish to have a high lift/drag ratio.
to my liking, a flying wing or even delta planform provide for those needs, unwanted, non-lift-generating drag of the fuselage is eliminated, flight can be very stable without additional non-lift generating surfaces, you'll build a very sturdy model without sacrificing weight for the fuselage, etc.check out the horten-designs on the web. If you have the time and resources, you may even experiment with a variable wing area, where additional (lift generating) surfaces are extended from the wing, e.g after a certain time has elapsed, or the speed has decreased to a set level.
Stay high

[Rocker]

Looks like an interesting discussion. Waiting for the pictures.