A new Scratch Built Flying Wing: The Raptor

 

The Nova is grounded while I figure out the APM troubles I'm having, see these posts for the details:

http://www.diydrones.com/group/apmusergroup/forum/topics/apparent-a...

http://www.diydrones.com/profiles/blogs/auto-land-testing-and-a-sad...

 

In the meantime, I'd like to announce the Raptor! It's going to be a 48 inch wing span flying wing designed after the very successful Ritewing Zephyr. If it performs well it will get an APM as well and be tested alongside the other airframes for efficiency/flight resilience.

 

Should be a great entry into flying wings and help me consider it as an option for my USA trip airframe. I'll build it, maybe maiden it next week!

 

-Trent

Views: 7919

Tags: Flying Wing, My Geek Show, MyGeekShow, Raptor

Comment by SaadTiwana on March 10, 2012 at 7:33am

Hi Trent, 

Hope your APM problems get solved soon. 
I've done 2-3 tries on flying wings. I designed all of them myself without following any plans...and i have to admit..none of them performed too great :( Or maybe it's my flying skills that weren't upto the task, since the flying wings turned out to be high-speed and i couldn't control them well :(

Anyway, knowing your talent, i'm sure your Wing will fly well :) Would you be sharing your plans with us like the Nova? Also, what type of characteristics are you expecting (mainly flight envelope,etc)?

Good luck btw!

Regards,
Saad 


Developer
Comment by Ryan Beall on March 10, 2012 at 9:48am

Don't use a clarkY for your airfoil.  Use a flying wing airfoil like the MH series.  The idea is you want to consider the moment coefficient of the airfoil.  A clark Y will have a significantly higher negative pitching moment coefficient than say one of the MH airfoils.  Flying wings are a balance of sweep, pitching moment coefficient, and center of gravity. The better you pick a foil and sweep design the less "recurve" you will have to generate via elevon deflection.

http://www.mh-aerotools.de/airfoils/mh32koo.htm

-Ritewing probably won't tell you what airfoil he uses but really you will be ok with almost anything other than a clarkY or anything with zero recurve and a ton of camber.  Hit me up if you have any questions

-Ryan


Moderator
Comment by Gary Mortimer on March 10, 2012 at 11:38am

Ryan is right, MH62 is the way to go. Make sure you do this bit http://fwcg.3dzone.dk/ standard platforms are very forgiving, wings will be pigs until you get the CG right. Most people that struggle need to put just a little more weight on the nose. Two servos only, how simple can you get ;-)

Here is how we laid out our last one

Oh yes, you will need to think a bit about motor mount angles you can end up with all sorts of weirdness ;-)

If you want to fold your own wing to experiment with try one of these http://www.mugi.co.uk/ there is a free plan there, I built a two meter wingspan one once they are great.

DO not build too heavy, it will be a pig to launch, 

Comment by Ramon L on March 10, 2012 at 12:17pm

When I see this kind of thread were everyone try to contribute with someones idea.. uff! DIY community rocks!

Trent about the APM I had a similar issue, contact customer service, explain them your problems as you have done here and believe me they will do their best to help you, send your board the service is fast and they always update you via email with the diagnosis and further steps to follow.

Since I'm also very interested in a flying wing, actually i'm planning to buy a Zephyr II for FPV , ill subscribe to this thread, keep it going!

Comment by Marko Kleine Berkenbusch on March 10, 2012 at 7:06pm

Hi Trent,

As always, I enjoyed your post. I really like your systematic approach at figuring things out... 

In line with some of the comments above: Clark-Y is not a good airfoil choice for a flying wing since it has a pronounced pitching moment. 

Have you looked at the program XFLR5 for designing your wing? Google it, it is a free program that allows to design and do very detailed analyses of model aircraft/wings. I designed and built a flying wing on it a while ago and its flight characteristics seem to match pretty well what the program predicted (well, at least as far as I can tell  - so that may or may not mean anything ;-) ). Here is a screen shot of the wing in XFLR5:

And this is what the (almost) final product looks like (I have added some foam pieces to blend the center box with the wings a little better):

The airfoil is cut out of foam and covered in fiber glass. I worked in a twist of about 5 degrees from the root to the tip - this adds a little to pitch stability. 

Anyways, I am sure you will figure something out that works for you, just thought I'd point you to a real cool and useful program...

Marko

Comment by Greg Fletcher on March 10, 2012 at 7:26pm

Gary is right. Don't use that airfoil for a wing. You need something like an MH62 or there about. You need to buy profili.

it's an air foil data base and simulator. It generates polar graphs and such.

Comment by Dez Socks on March 10, 2012 at 8:39pm

Thanks for the video,simplifies how to build a wing from scratch.Cant wait to see your wing.

Comment by Trent at MyGeekShow on March 10, 2012 at 9:16pm

DIYD Team: You guys are awesome. I apologize for the delayed response... today has been very busy.

 

I've never had such a difinitive response before: No Clark-y on a flying wing! Thank you everyone for steering me in the right direction. I'll consider closely all the options and suggestions you all have made, it will take a couple days, there is a lot to review!

 

Thank you again for your all your support. Ramon got it right: "When I see this kind of thread were everyone try to contribute with someones idea.. uff! DIY community rocks!" I couldn't agree more.


-Trent


Developer
Comment by Ryan Beall on March 10, 2012 at 9:26pm

Don't forget to add twist also!  The tips should drop a few degrees.

Comment by SaadTiwana on March 10, 2012 at 9:51pm

@Ryan, Marko : How do you add the twist to the wing while cutting it out of foam? I generally cut wings using hotwire (which is what most people do, i think). Kindly tell me the way to incorporate twist in the process.

Thanks

Saad

Comment

You need to be a member of DIY Drones to add comments!

Join DIY Drones

© 2014   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service