HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old May 26, 2009, 11:33 PM
PunchDrunk ex-Pug try'n fly'n
jp.electrik's Avatar
United States, MN, Minneapolis
Joined Jan 2009
1,014 Posts
Quote:
Originally Posted by Lee
I decided for fun to set one as a flying wing and fly with elevons and a fixed tail.
Lee, Mine flew well until I had to change the motor and consequently the CG. I never found the new CG with the lighter motor. I am dying to hear where yours ends up. jp
jp.electrik is offline Find More Posts by jp.electrik
Reply With Quote
Sign up now
to remove ads between posts
Old May 27, 2009, 12:46 AM
Lee
PERFECT LANDING !!!
Lee's Avatar
USA, UT, Orem
Joined Jul 2004
9,254 Posts
By my calculations the CG won't change even though i am flying with elevons rather than elevator ailerons. Only test flying will tell.
Lee is offline Find More Posts by Lee
Reply With Quote
Old May 27, 2009, 04:12 PM
Registered User
derJuF's Avatar
Lahr / Germany
Joined Jul 2006
142 Posts
Quote:
Originally Posted by bluefalconhollan
You made a really nice movable tail! Today I added a video of the flight of the bald eagle:

http://vimeo.com/4841183
..thank You I love your flapping Bald eagle!

The first testflight of mine was sucessful, after locating the right cg i can steer perfect up/down/left an right.
One of my next projects will be a ornithopter model (...perhaps a bat with 80cm Wingspan and red glowing eyes for confusing my neighbours ) but first i have to finish the current bird and make a video of it.

greetings juergen
derJuF is offline Find More Posts by derJuF
Reply With Quote
Old May 27, 2009, 11:52 PM
Lee
PERFECT LANDING !!!
Lee's Avatar
USA, UT, Orem
Joined Jul 2004
9,254 Posts
Here is proof of concept.
The EPP Peregrine flies well without the elevator.


The advantages are....

The elevator servo is no longer needed. This saves weight and cost.
The elevator servo has had high the highest stress and had the biggest likelihood of broken horns and gears.
The plane is easier to fly and tends to be more gentle. I handed the transmitter to a 1 month flyer who said it was easier to fly than his flying wing.

Disadvantages ???

Harder to get the tail glued in the exact position for flying. I might make it adjustable like the Q-Planes
The separate elevator looked cool.
Some of the extreme stunts that came from the big tail will not be possible.

Note.... I made a typo in the video. Crashtesthobby is @gmail.com not @gmail.org.

The video is a little overexposed and the bird appears white. The paint on the Peregrine looks great with the multi-tone paint. Wish it showed up better.

Peregrine with Elevons 5-09 (4 min 10 sec)
Lee is offline Find More Posts by Lee
Last edited by Lee; May 28, 2009 at 01:23 PM.
Reply With Quote
Old May 28, 2009, 05:10 AM
PunchDrunk ex-Pug try'n fly'n
jp.electrik's Avatar
United States, MN, Minneapolis
Joined Jan 2009
1,014 Posts
Aha! I had not considered keeping the tail as an H stab.
Mine was H-stab-less.
That should make it much more stable, but yes, a bit less aerobatic.
Awesome Lee! jp
jp.electrik is offline Find More Posts by jp.electrik
Reply With Quote
Old May 28, 2009, 12:58 PM
Lee
PERFECT LANDING !!!
Lee's Avatar
USA, UT, Orem
Joined Jul 2004
9,254 Posts
JP - A comment you made a long time ago was the motivation for trying the elevons.

The plane still needs to look like a bird. The tail helps.

This video was shot a couple of months ago with the old Peregrine set up on the thin wing. I fly these planes a lot. My brain likes to see them in the air.

EPP Peregrine at the Practice Field. (3 min 23 sec)
Lee is offline Find More Posts by Lee
Last edited by Lee; May 29, 2009 at 01:14 AM.
Reply With Quote
Old May 28, 2009, 01:15 PM
Dance the skies...
Tom Frank's Avatar
United States, MA, Walpole
Joined Dec 2003
17,893 Posts
Quote:
Originally Posted by Lee
Here is proof of concept.
The EPP Peregrine flies well without the elevator.
Neat! Now who wants to try elevon-only flying with the FFF eagle? If I had a bashed-up one I would do it.

I have done some flaperon testing with my eagle, and dropping both warperons (ailerons with outer end fixed at neutral) 30% with no elevator correction results in a sharp dive. 20% up correction on the V-tail surfaces is needed to fly level with that flaperon setting. I'd assume it would be similar in reverse. And seeing how well the eagle turns with warperons alone and how nasty rudder action is with the V-tail (more roll and dive than skid turn), maybe an elevon-only eagle is viable.

Gain: Perhaps none if your eagle has no dual-servo ailerons , but if it does, you can eliminating two servos, simplify the build, and drop back to a less expensive 4CH RX.

Loss: Perhaps little or none. Although an aileron eagle with V-tail is capable of some simple aerobatics, that certainly is not it's primary flight envelope. It may do just as well with elevons only.
Tom Frank is offline Find More Posts by Tom Frank
Last edited by Tom Frank; May 28, 2009 at 01:30 PM.
Reply With Quote
Old May 28, 2009, 01:24 PM
Lee
PERFECT LANDING !!!
Lee's Avatar
USA, UT, Orem
Joined Jul 2004
9,254 Posts
They are flying a lot of flying wings with the KF airfoil. It should work fine if you get the CG right.

I like the variety of this thread!!!!
Lee is offline Find More Posts by Lee
Reply With Quote
Old May 28, 2009, 03:50 PM
More Motors, More Fun... :-)
nioa's Avatar
Phoenix, AZ
Joined Jan 2008
698 Posts
Another EPP Peregrine Falcon about to fly.

Just finished this up and I am looking forward to a maiden flight. My build details are on my blog (you may have to scroll down a little).

I think that I would like to try the elevon version. A fixed tail would simplify things.

The graphic design was done by a local artist, she used water-color paints, and markers. It added no weight at all.

Mattie showing off the falcon.
nioa is offline Find More Posts by nioa
RCG Plus Member
Latest blog entry: VQ Models T-34 Mentor 61.4"...
Reply With Quote
Old May 28, 2009, 05:08 PM
PunchDrunk ex-Pug try'n fly'n
jp.electrik's Avatar
United States, MN, Minneapolis
Joined Jan 2009
1,014 Posts
You have a good memory Lee. I did get my falcon Wing to fly until a motor issue forced me to make a change causing the CG to shift. I lost patience before I found the new CG. Mine had very little tail, static of course. She looked and flew great. I just grew tired of the R&D which was depleting my motor supply. I lost patience with the tractor prop, I wonder if a push confg. is possible?
Here is a shot of her from last Fall. jp



BTW; Judy rocks IS She available for other work?
jp.electrik is offline Find More Posts by jp.electrik
Last edited by jp.electrik; May 28, 2009 at 05:28 PM.
Reply With Quote
Old May 29, 2009, 12:59 AM
Lee
PERFECT LANDING !!!
Lee's Avatar
USA, UT, Orem
Joined Jul 2004
9,254 Posts
Here is something TJ and I have been working on. I keep trying to get a bird look on one of my flying wings.

http://www.rcgroups.com/forums/showthread.php?t=1052384
Lee is offline Find More Posts by Lee
Reply With Quote
Old May 29, 2009, 01:09 AM
Lee
PERFECT LANDING !!!
Lee's Avatar
USA, UT, Orem
Joined Jul 2004
9,254 Posts
Quote:
Originally Posted by nioa
Just finished this up and I am looking forward to a maiden flight. My build details are on my blog (you may have to scroll down a little).

I think that I would like to try the elevon version. A fixed tail would simplify things.

The graphic design was done by a local artist, she used water-color paints, and markers. It added no weight at all.

Mattie showing off the falcon.

The plane looks great!!!!

The videos I just posted are stock kits checking out the kits.
Lee is offline Find More Posts by Lee
Reply With Quote
Old Jun 02, 2009, 02:00 PM
More Motors, More Fun... :-)
nioa's Avatar
Phoenix, AZ
Joined Jan 2008
698 Posts
EPP Peregrine Falcon with Elevons

I reconfigured the EPP Peregrine Falcon with elevons.

The maiden flight was good, in fact, very enjoyable. The plane tracked well. The hardest thing (which was really not that hard) was to figure out the best position for the now fixed tail (because of the complex shape of the tail, it is hard to tell if the tail is "level" with the fuselage).

Before I flew her with the new elevons, I balanced the bird from the ceiling (I used about 2 feet of string attached to the bird and the ceiling) on her CG and powered her up slightly. This allowed me to roughly set the angle of the tail by observing how the fuselage would deflect up or down. This got me into the "ballpark" enough so that I felt confident that the bird wouldn't tip up or down excessively on her first actual flight.

Initially, I set the angle of the tail at what I thought was "in line" with the fuselage, then I used the method above; it turned out that the tail angle pitched the fuselage up excessively. Lowering the tail resulted in a "straighter" thrust vector (naturally, the bird is going to try to pivot around the hanging point, so this method has its limitations, but it does seem to get you into the "ballpark").

My "guess-ta-mate" was close enough;, the bird did pitch up slightly even though the tail "looked" like it was slightly in "down" elevator position (better to pitch up, then pitch down ). I will fine-tune it later.

A great bird, now even better!

See my RCGroups blog for more pics and details.

Quote:
Originally Posted by Lee

The advantages are....

The elevator servo is no longer needed. This saves weight and cost.
The elevator servo has had high the highest stress and had the biggest likelihood of broken horns and gears.
The plane is easier to fly and tends to be more gentle. I handed the transmitter to a 1 month flyer who said it was easier to fly than his flying wing.

Disadvantages ???

Harder to get the tail glued in the exact position for flying. I might make it adjustable like the Q-Planes
The separate elevator looked cool.
Some of the extreme stunts that came from the big tail will not be possible.
nioa is offline Find More Posts by nioa
RCG Plus Member
Latest blog entry: VQ Models T-34 Mentor 61.4"...
Reply With Quote
Old Jun 02, 2009, 02:38 PM
PunchDrunk ex-Pug try'n fly'n
jp.electrik's Avatar
United States, MN, Minneapolis
Joined Jan 2009
1,014 Posts
[QUOTE=nioa]I reconfigured the EPP Peregrine Falcon with elevons.
....Lowering the tail resulted in a "straighter" thrust vector ....I will fine-tune it later.....A great bird, now even better!

Great work, nioa!
The more you can fine tune the angle of incidence the faster and more efficiently She will fly. You might find the Dive Test helpful, I certainly do.
I'm sure you are familiar with it but here it is anyway...
Get Her trimmed so She will fly level with 50% or less throttle.
Cut throttle and put Her into @45 deg dive.
If you have the CG and trims right She should not change attitude and remain at the same angle She started the dive at. If She noses up you have the CG forward and/or the angel of incidence to high.
The perfect CG with the perfect Angle of Incidence will hold the same dive angle during the test. This will give you; less drag, more speed, better efficiency.
Great work! It appears I could have used a bigger H-stab in my efforts with the "Flying Wing Falcon". Probably looks better too!
jp
jp.electrik is offline Find More Posts by jp.electrik
Reply With Quote
Old Jun 02, 2009, 05:51 PM
OOPS
Manta1's Avatar
USA, GA, Cochran
Joined Jun 2008
20,174 Posts
persubscibed
Manta1 is offline Find More Posts by Manta1
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Why aren`t most foam planes made with EPP or equivalent. Scarey Foamy EDFs 1 Jul 24, 2007 11:20 PM
Planes Built With EPP And Depron. What Would Be Your Favorite. jbj620 3D Flying 10 Dec 05, 2004 08:06 AM
Rave Before n After My new war bird P-51 Mustang(EPP) powder Slope 22 Aug 22, 2003 02:27 PM
hey guys if yous are looking for arf war bird planes seafire Foamies (Kits) 5 Mar 10, 2002 06:41 PM