HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Nov 26, 2012, 04:54 PM
Registered User
LuvEvolution7's Avatar
St.Catharines, Ontario
Joined Jan 2009
10,377 Posts
I'd prefer my thrust line above the center line than below it. my preference would be slight back pressure with power than down pressure.
LuvEvolution7 is offline Find More Posts by LuvEvolution7
Reply With Quote
Sign up now
to remove ads between posts
Old Nov 26, 2012, 10:22 PM
Registered User
Rocketboy1030's Avatar
Canada, ON, Mississauga
Joined Nov 2011
130 Posts
Okay so the 3 Maiden attempts are not good , but it is still in one piece. The EDF tube had enough power to drive itself around the delta in tight circles, awesome 3D performance but not what I was looking for. I think I am way off in my C of G , I had a friend calculate my wing shape in CAD for 22%, but now I am thinking more like 15% might be better on a high rake delta. Nobody publishes data on these things , and I defaulted to make my EDF tube parallel to the wing.At the end of the throw , it climbed out into a stall and then looped non stop until I powered off.LuvEvolution, many guys gearing up and testing for Ottawa next year, but it will be some sort of scratch build that will take it....
Rocketboy1030 is offline Find More Posts by Rocketboy1030
Reply With Quote
Old Nov 26, 2012, 10:39 PM
Registered User
LuvEvolution7's Avatar
St.Catharines, Ontario
Joined Jan 2009
10,377 Posts
I agree, it'll be a scratchbuilt that'll take it.....................and someone who has the biggest understanding of aerodynamics. not sure that'll be me, but I'm gonna give it my best shot. LOL.

does your delta have a nose/fuselage section, or is is a straight delta wing? if it's a wing, 22% sounds way to far back. it could also be that your thrust line is not in line with the centerline of the fuselage/wing. if one of those two don't jive, you end up with that looping, 3D flight. add to that a CG that's too far back and you combine tail heavy with it. I bet it looked really cool though. LOL.

Rich
LuvEvolution7 is offline Find More Posts by LuvEvolution7
Reply With Quote
Old Nov 27, 2012, 04:26 PM
Registered User
Lt599's Avatar
United States, WA, Shelton
Joined Feb 2012
613 Posts
I havent looked at the thread in awhile but I have some interest in building another experimental project. Is the speed contest open to all or are you guys designing for a local contest? I designed and built the Vixen XD1 awhile back. It is a delta with a 70mm on 5s, it is fast but I have never GPSed or radared it. I have been thinking of a modified design built specifically for speed. Heres a pic from the build thread.
Lt599 is offline Find More Posts by Lt599
Reply With Quote
Old Nov 28, 2012, 07:16 AM
Registered User
USA
Joined Apr 2007
2,384 Posts
speed

I whould move fan forward & add thrust tube
space 1 is offline Find More Posts by space 1
Reply With Quote
Old Dec 01, 2012, 11:46 AM
Registered User
Holland
Joined Apr 2003
132 Posts
this could also be the way to mount the elevator not to close the wing, make it a canard.
found it in the luft46 article

Hoeby is offline Find More Posts by Hoeby
Reply With Quote
Old Dec 01, 2012, 01:00 PM
Registered User
USA
Joined Apr 2007
2,384 Posts
just build delta wing & see how munch power you can punt on it
space 1 is offline Find More Posts by space 1
Reply With Quote
Old Dec 01, 2012, 04:36 PM
My project: FAIREY DELTA 1
Erik v. Schaik's Avatar
Uden Volkel, Netherlands
Joined Dec 2003
4,974 Posts
Discart the delta wing because the sensitivity at high speeds are close to uncontrolable, even with dual rate, expo,glass hing lines and large surface levers.

Been there in 2006:
http://www.rcgroups.com/forums/showthread.php?t=558138
Erik v. Schaik is offline Find More Posts by Erik v. Schaik
Reply With Quote
Old Dec 01, 2012, 06:35 PM
Registered User
LuvEvolution7's Avatar
St.Catharines, Ontario
Joined Jan 2009
10,377 Posts
agreed. Delta's are cool, but they scrub too much darn speed to be in a speed contest. you need more brute power to get back the speed you scrub off. sure, they go like a bat outta hell in a straight line, but you gotta take too much real estate to build up the speed you lost in the turn to get there. small airframe with lots of power will win a speed contest. a DS-style airframe is what will win it.
LuvEvolution7 is offline Find More Posts by LuvEvolution7
Reply With Quote
Old Dec 01, 2012, 09:12 PM
Registered User
Lt599's Avatar
United States, WA, Shelton
Joined Feb 2012
613 Posts
Whats a DS style airframe?
Lt599 is offline Find More Posts by Lt599
Reply With Quote
Old Dec 01, 2012, 09:14 PM
Lee Liddle
Knife Liddle's Avatar
Carrollton, Tx
Joined Dec 2006
7,833 Posts
Dynamic Soaring
Knife Liddle is online now Find More Posts by Knife Liddle
RCG Plus Member
Old Dec 01, 2012, 09:19 PM
Lee Liddle
Knife Liddle's Avatar
Carrollton, Tx
Joined Dec 2006
7,833 Posts
I've had good luck with flying wing designs. Not pure deltas but more like blended wing/fuselage designs. With the right airfoil and thrust angle, much of the drag can be reduced.
Knife Liddle is online now Find More Posts by Knife Liddle
RCG Plus Member
Old Dec 01, 2012, 09:36 PM
Registered User
LuvEvolution7's Avatar
St.Catharines, Ontario
Joined Jan 2009
10,377 Posts
did you get my PM Lee? what about a wing like that, on a DS style fuse? might be onto something there. LOL.
LuvEvolution7 is offline Find More Posts by LuvEvolution7
Reply With Quote
Old Dec 02, 2012, 02:50 AM
My project: FAIREY DELTA 1
Erik v. Schaik's Avatar
Uden Volkel, Netherlands
Joined Dec 2003
4,974 Posts
The 1st Uriah concept (Uriah-B1) was a flying wing based on a design winner contest plane called Tsunami. Links and plans of the Tsunami can be found at post4 of the Uriah-B1 thread:
http://www.rcgroups.com/forums/showthread.php?t=1056417
Tough the Tsunami should be an exellent flyer with 480BB power, On brushless it showed several issues. I think The original plans may work very well on a 250w setup which is not high speed but still a good pace. i think it can be very close to the 1st gen Nid powered Pyranhas.

Having build 3 lippischP20 and the Uriah-B1 gives me good experience in flying wings. Especially the Uriah-B1 showed loss in height when cornering and low high speed fly bys were hard to control regarding elevator. Because of this I added the stab and relocated the fan.

In the link you can see the modified thrust tube angle on the Uriah-B1. The angle made a handlaunch impossible because eventually it went down due to coupling.
Erik v. Schaik is offline Find More Posts by Erik v. Schaik
Reply With Quote
Old Dec 02, 2012, 03:14 AM
My project: FAIREY DELTA 1
Erik v. Schaik's Avatar
Uden Volkel, Netherlands
Joined Dec 2003
4,974 Posts
Quote:
Originally Posted by Lt599 View Post
Whats a DS style airframe?
http://airtoimedia.nl/web/upload/Emi...k_8-7-2007.wmv

Makes great sport flyers. The Destiny became my favourite everyday edf jet but the RG15 airfoil is not a high speed critics choice. This is a NIB glass version purshased 2nd hand. I ordered a carbon version a week earlier which has not been in production yet (roumor is 10 months waiting time). Feel free to send me a pm if interested. The carbon versions are priced very sharp!
Erik v. Schaik is offline Find More Posts by Erik v. Schaik
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion How do you guys feel about Nitroplanes? (The company) rckatz Nitro Planes 36 Nov 29, 2012 04:33 PM
Question Question about flying wing CG and how it might be affected by adding a fuse daronj Foamies (Scratchbuilt) 2 Jul 01, 2012 01:10 PM
Contest Hobby Lobby Lynx Speed Contest!!!! CONTINUED NEW Current top speed is 139.6 mph! dpowellmeii Pusher Prop Jet Models 7 May 21, 2012 11:52 AM
Rave How about a Tiger Moth gliding contest? swooper GWS (Grand Wing Servo) 3 Nov 08, 2003 03:09 PM