Espritmodel.com Telemetry Radio
Reply
Thread Tools
Old Feb 01, 2013, 12:06 AM
Build something.
Nodd's Avatar
United States, CT, Fairfield
Joined Mar 2012
668 Posts
Build Log
Nodd's Plank



I'm interesting in doing some slope-soaring however our closest spot, on the Hudson River, has a tree-line that you have to get above before you reach the lift. We usually fly electric Easy-Gliders, stuff like that there, as you need something powered to get into the lift. That's fun-n-all but I wanted something a little more sporty than an Easy-Glider. So I've design this goofy little EDF powered plank to fool around with.

The following will document the build, subscribe if you'd like to follow along.

The design is centered around this little 55mm HobbyKing electric ducted fan...



The EDF will be buried in the rear of the fuselage with large intakes both above & below the wing...



I'm planning to build with wing from the following materials using a symmetric KF stepped airfoil...



I'm going with a four servo wing so I can get crazy mixing some airbrakes & other nuttiness...



Well that's the plan for now. This should be a cool little project, doesn't have to be perfect, fun is the main goal. As with all my builds, I welcome comments & advice...

Nodd is offline Find More Posts by Nodd
Reply With Quote
Sign up now
to remove ads between posts
Old Feb 01, 2013, 01:07 AM
Hunting for Goat Lifters
Titus ZA's Avatar
South Africa, GP, Randburg
Joined Jul 2012
109 Posts
Now this looks seriously cool, like sub zero cool!

Subscribed!

Cheers
T
Titus ZA is offline Find More Posts by Titus ZA
Reply With Quote
Old Feb 01, 2013, 02:51 AM
Registered User
LudwigB's Avatar
South Africa, GP, Pretoria
Joined Jan 2012
97 Posts
Looks like this one might go to 11! :O)
LudwigB is offline Find More Posts by LudwigB
Reply With Quote
Old Feb 01, 2013, 08:38 AM
Registered User
Gordysoar's Avatar
USA, KY, Louisville
Joined Oct 2002
682 Posts
Use Elevons!

Don't split the elevons into ailerons and elevator!

At low speed the elevators are blocked and you need a lot more deflection to do the job which usually leads to stalls and walks down the slope.

You are going to find that the duct causes a LOT of drag but the project looks fun.

If you want to use use the inboard parts of the elevons as drag brakes to slow landings, make sure they 'pop' down close to 90 and you shouldn't have any pitch change. They'll need to pop back up to normal also Landing FLAPS don't work on wings.

Mixing them will be interesting., But if you set them up as landing flaps but assigned to an off on switch, you can mix in camber pump to elevator both neg and pos so that they also work with the elevator function, you don't need them to be aileron inboard.

Gordy
Gordysoar is online now Find More Posts by Gordysoar
RCG Plus Member
Reply With Quote
Old Feb 01, 2013, 08:47 AM
fast,,,, faster
FASTBEN's Avatar
KELLER TEXAS
Joined Feb 2002
3,402 Posts
Subscribed!
FASTBEN is offline Find More Posts by FASTBEN
Reply With Quote
Old Feb 01, 2013, 09:40 AM
Red Merle ALES
Curtis Suter's Avatar
United States, Mt, Helena
Joined Apr 2002
5,313 Posts
Nodd,

You're a computer artist!

What airfoil are you planning on using?

I like your idea of the four servo wing. If your landing flaps/speedbrakes don't work out you can always mix them as if you have a two servo wing. I do know with swept wings you can have very effective flaps at all angle of deflection as you just raise the ailerons to counteract the pitching moment the flaps cause. With a plank I have no experience with that.

I see you posted here in the electrics, I'd suggest this forum as you may get more advice:
http://www.rcgroups.com/flying-wings-211/

Lastly, check out this video at about 1:30 time into the video of flap deployment. This is Tinamou a swept flying wing I scratch built based off of Dr. Panknin's Flying Rainbow. Notice the pitch change with flap application.
Tinamou Compilation (1 min 45 sec)


Subscribed.
Curtis
Curtis Suter is online now Find More Posts by Curtis Suter
RCG Plus Member
Reply With Quote
Old Feb 01, 2013, 11:52 AM
Registered User
Black Cloud's Avatar
Joined Apr 2009
95 Posts
Very nice concept Nodd!
Good luck with this project

Sjaak
Black Cloud is offline Find More Posts by Black Cloud
Reply With Quote
Old Feb 01, 2013, 01:09 PM
Build something.
Nodd's Avatar
United States, CT, Fairfield
Joined Mar 2012
668 Posts
Awesome feedback, thanks folks.

Over on one of my mirror threads its been suggested that my carbon-fiber spar could be improved & have to agree. As soon as I ordered it I realized I should probably have gone with a vertically oriented spar & not horizontal. So I ordered some slightly different carbon-fiber...



One spar instead of two maybe all I need, I'll make that call once the wing is together & I can gauge its rigidity.

Thanks for the video Curtis. Yeap that's exactly what I had in mind for air-braking & is why I went with a four servo wing...



I expect it'll take some fine tuning to get the deflection angles right but from what I've seen, this is the way to stop a plank. BTW I LOVE the drag-shoot, that's too cool.

Okay well this is sounding good. I hope to begin construction soon. Stay tuned.
Nodd is offline Find More Posts by Nodd
Reply With Quote
Old Feb 02, 2013, 09:21 AM
Registered User
Joined Oct 2012
18 Posts
Very cool Nodd, I followed your last scratch build electric glider and it absolutely amazed me. I cant wait to see where you go with this one. I used to build longbows and other traditional archery equipment, built my trainer from a kit (telemaster 40) and if I'm not careful, I'll have to start scratch building planes too. We have a guy in our club that just got a laser engraver so home built ribs and other parts are well within my reach.

Anyhow, looking forward to following this build.

Phil
rctmpilot is offline Find More Posts by rctmpilot
Reply With Quote
Old Feb 02, 2013, 09:19 PM
Build something.
Nodd's Avatar
United States, CT, Fairfield
Joined Mar 2012
668 Posts
Sounds like you already have the skills & the equipment. Go for it Phil.

Design in progress
Based upon feedback here on the forums I've made a few tweaks to the design. First is more vertical fin area...



It was also suggested that I also move the duct intake forward a tad...



So here's the latest & greatest...



Thanks again for the input.
Nodd is offline Find More Posts by Nodd
Reply With Quote
Old Feb 02, 2013, 09:29 PM
Sure it'll work
Flyextreme's Avatar
United States, CA, Torrance
Joined Nov 2005
4,270 Posts
Very cool project, and design for sure.

I'm no expert, but unless your EDF/motor have some substatial weight, it looks as though the foreward lipo placement would make it very nose heavy.....just sayin'
Flyextreme is offline Find More Posts by Flyextreme
Reply With Quote
Old Feb 02, 2013, 10:10 PM
Build something.
Nodd's Avatar
United States, CT, Fairfield
Joined Mar 2012
668 Posts
Glad you like it. Yeah, hard to say where the CG will end up but there's room in the fuselage to swap stuff around if need be.
Nodd is offline Find More Posts by Nodd
Reply With Quote
Old Feb 04, 2013, 12:01 PM
Registered User
Joined Mar 2008
627 Posts
Neat looking plane.

I am skeptical about the KfM section (I have followed several KfM threads) although I would speculate that in regimes where you have "energy to waste" (like slope) they may be a good fit (assuming control isn't compromised by the square edges, etc. I am interested to see what your experience brings. I hope you consider sharing and post your flight "logs" here or in the Nurflugel subforum.

You may want to consider some sweep to improve sensitivity to CG but that may also be a consideration for a second version of the plane.

Good luck.
Cap_n_Dave is online now Find More Posts by Cap_n_Dave
Reply With Quote
Old Feb 04, 2013, 03:08 PM
ulpilotrmh
ulpilotrmh's Avatar
USA, FL, Tavares
Joined Sep 2010
339 Posts
Subscribed!
ulpilotrmh is offline Find More Posts by ulpilotrmh
Reply With Quote
Old Feb 04, 2013, 10:09 PM
Registered User
doc993's Avatar
United States, WI, Stoddard
Joined Dec 2009
1,105 Posts
I'm in, subscribed.
doc993 is online now Find More Posts by doc993
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Build Log Nodd's Airboat Nodd Racing Boats - Electric 34 May 08, 2014 12:04 AM
Discussion "Plank" wings and pendulum stability derp express Modeling Science 30 Mar 02, 2013 07:45 PM
Question Wing tips on a plank Stupot46 Slope 3 Feb 16, 2013 12:10 PM
Discussion Straightening a warped balsa plank/wing? C₄H₁₀ The Builders Workshop 8 Jan 07, 2013 12:26 AM