Discussion Canard Forum: Show,Discuss, Learn

[canard addict]

This thread is for present and future canard lovers to show pictures, tell of their experiences or just ask questions about the techniques of building a successful canard. There seems to be a growing interest in canards. Sig had the Tri-Star, Multiplex,the Sonic Liner,Raidentech and Richmodels, the Long EZ and Quickie,Gunderson Aero, the S1 slope soarer and Hobby Lobby, the Shinden to name a few. There are always questions about the center of gravity and many models have been damaged before finding it. I will start by showing my first canard, The GWS Slow Stick conversion. It was built in haste in 2004 when I was anxious to put my new found knowledge to work from a book by Andy Lennon entitled "The Basics of Model Aircraft Design". It is from the publisher of Model Airplane news, Air Age Publishing Co. The Slow Stick is probably the most popular ARF which is suitable for canard conversion. The GWS Pico Stick, the Wingo from Hobby Lobby and the Soar Star are also good candidates. My GWS Slow Stick had the EPS 300 geared motor with the 11-8 orange prop. The model flew like a dream. It always pleases the onlookers and I love to share the controls with other modelers. I will attach pictures here and hope to provide all the details of construction. Build Logs index six models: Page 182, post 2723

[willhaney]

That just looks so cool. How does it fly?

[canard addict]

Thank you! I flew it Sunday in 5mph wind and I got a renewed interest in it. It is 39.5 inches long and penetrates incredibly well. We looped, flew inverted made graceful turns, held full UP elevator and watched the nose act like it was riding ocean waves. The landing, as always, was smooth with moderate power. The fuselage is 39.5" long. Get an extra fuselage and cut the required add on piece which will measure about 8" long. There is a plastic piece in the kit which can be used to join the fuselage sections together. It may help to add a bit of canopy glue to the joint although I did not. The joint should be located under the main wing roughly 3.5 inches behind the LE. Be sure to slide the leading edge wing mount onto the longest fuselage part before glueing the splice. The wing is mounted as far back to the motor as possible with the leading edge higher than the trailing edge or with a positive incidence. The landing gear is stock but the wheels will not carry the load. I used the Maxx Products wheels 2-1/2" with the 2 inch plastic one on the front. These cut through the grass well. Charles

[Skrogg]

Awesome Charles.
How does your wing bracing work for ya?
Is CG in the same place as a stock ss?
I've been wanting to build a pusher.

[canard addict]

Thanks, Skrogg, If you will search for "canard center of gravity calculator", and fill in the blanks, you will find the COG which has always worked for me. The wing tips will flutter when speed is raised. To correct this, I added crossed 3/16 by 1/8 balsa sticks as shown. It then became a different plane for flying fast and will even do a sloppy roll. I slotted the sticks in and glued them at the cross point. The ailerons were cut out as outlined on the wing. I used 3M and even some Scotch tape for hinges. I recommend 3M Blenderm which I get from Model Airplane Engineering 770-925-8326. The Aileron servos need to weigh no more than 0.32 ounces since weight always needs to be saved at the rear of a canard. Hitec 55 servos are good. Mine are GWS Pico Std. Just rough sand the servo and attach with canopy glue. The Pixie 20 ESC is attached to the front wing mount with double sided tape.I plugged the throttle control wire onto the receiver and mounted it with velcro as far forward as the wire would reach. An 11" Y harness brings the ailerons to the receiver. The center of gravity is 21-3/8 inches from the canard leading edge. Charles

[tometech]

How do you build the canard? size shape and form?

Tom

[canard addict]

The canard wing must be 120 sq. inches. It is 24" span with 5" chord. I also use the Parkzone J3 Cub wing as a canard which will be described later. To build the balsa wing, I cut a 12 by 5 piece from 1/32" sheet balsa and pinned it flat to the board. Glue a 1/8 Sq. balsa leading edge on top of the sheet and flush with the edge. Measure back 1-1/4 inch from the LE and glue a 1/8 by 1/2 balsa spar in the vertical position. This is at the highest point of the wing crest. There are four 1/8 thick ribs.One at each end and two in between. The elevator measures 11 by 1-3/4 and will require the framing in with rib tips and spars. The ribs are 3/16 tall at the front so that the 1/32 top sheeting will form a neat rounded LE. Use your skills to build the wing as you wish.Each tip is raised by one inch for dihedral or just pin down one wing to the board and raise the other tip up by two inches. The trailing edge of the wing is 1/16 thick formed by the two 1/32" sheets. I added a rib to the inboard side of the elevator and beefed up the center section a bit. The canard LE is raised by 0.4" above the TE with a balsa triangular block. The 1/2" wide block is mounted to the fuselage with epoxy at 0.3" behind the front. Use rough sandpaper to scratch the fuselage top for better adhesion. A 1/8 by 1-3/4 by 5 balsa platform was glued to the top of the 1/2" wide wedge.Be sure the grain runs with the wing length. The canard was glued to the platform with 1/32" by 5" strips added as dihedral shims. PLEASE NOTE!! Be sure to add the plastic battery holders, the servo holders and antenna holder onto the fuselage before mounting the canard. The canard has tiplets which are there to prevent tip vortices. they are supposed to prevent the high pressure air under the wing from getting to the low pressure air above. They cap off the tips and look good. Mine are too small and I have learned to make them larger with raised pointed tips and painted red for visability. See the CANGO.The elevator controls will follow. Charles

[cwesh]

I will toss in a few words about my canards.....

I started the original Starliner design way back in 1979, it was a flop, or should I say, that it did a nice figure 9 loop from takeoff!

After that, the design stayed "on the shelf" until late in 2003, when I got the Andy Lennon book and tried again!

The final version show here, was first flown in July of 2004, the original plane started out with a O.S. .45 fsr engine and flew that way for about 50 flights, it is called the Starliner Mk III. (Mk II never got off the drawing board) It has a 61" main wing span and weighs in at 6 lbs. It has proven to be a fine flyer.

Next I enlarged the plans to a 74" main wing span, powered by a .91 engine, and retracts. It came in a 9.5 lbs. This one is my favorite, it is a blast to fly, stable, responsive and really rips up the sky.

After that, I reduced the plans to an electric version, 48" span and a geared Himaxx motor, as with the others, worked great!.

So far, all the planes had one thing in common, no rudders. I tried several varations on the Mk IV, but all attemps failed, they all fluttered, due to the close proximity of the propellor to the rudders, at least I did not lose the plane, testing this! Final results is the the single engine version will not have rudders......

On the other hand, the twin......

I took the original prototype plane and swapped the glow engine out for a AXi outrunner (4120-18, 13x8 prop, 6s lipo) That one flew even better than the glow version. (Still a single motor plane!)

Since I could not leave well enough alone, I removed the single motor and took a pair of AXi 2814-12 outrunners and created motor mounts on the leading edge of the main wing, they are running 9x6 props on 3s lipo. So far during all of these mods the weight stayed right at 6lbs.

The twin flies great, best power so far. One of the other changes I did was to add rudders. With no prop interference, they work great, in fact too great. I was able to over do a knife edge too close to the ground and stalled the vertical stabs, which caused the plane to cartwheel across the sky. At 50ft off the ground, I was too low to recover. Damage was not too bad, the main wing was not damaged at all. (pictures below show the damage)

All in all, these plane are fun!

Pictures:

#1: Mk IIIa, single engine .45 glow.
#2: Mk III Twin, prior to crash.
#3: Mk III Twin, crash damage.
#4: Mk III Twin, all fixed!
#5: Mk IV on the runway!
#6: Mk IV flying!
#7: Mk IV flying!
#8: One of the original pictures used to create the "flying" effect

As to the future, I am planning on converting the Mk IV to twin electric! Geared brushless with 8s M1 cells. (A123) Predictions are looking like it should be slightly more than 1:1 thrust ratio. Should be fun!

Also, have been tinkering with a twin EDF version of the Mk III......we will see!

Later!
Chuck...

[BeavrdamElectric]

I've built a few recently, starting with the FoamEZ design from GPW, but I used a rudder instead of ailerons. It's 30". The next one was a larger (floater) 40" version to put a gear drive CD motor on. Lately I've gotten creative and used a bent dowell with three discs, I don't know what to call it. And then there's the Viggen. I'm still working on that one, I think I've got it about worked out (CG and throw issues). That one ought to be a nice little speedster, I'm hoping 50ish (fast for me).

I'm thinking about doing another FoamEZ without dihedral but still using the rudder and a taller fin. I think it will work, I need to try a small glider first.

Good Luck!

[canard addict]

Cwesh, Thanks for the great contribution! I know you must draw a crowd when you fly. What do you use for construction materials? I added a rudder to the nose of my Egret. It is good for turns with level wings,90% knife edge and stall turns. I have tried to push it into loss of control but apparently the rear winglets hold it stable. Why don't you come to the SEFF in 2007? You would certainly make the films and magazines! They are looking for up front new designs like yours. Charles

[cooper998]

I first saw a Canard aircraft fly many years ago at the Laser invitational airshow in Sussex NJ. Leo Loudenslager flew a Rutan Long EZ in a beautiful aerobatic display ending with a power off energy management glide and perfect touchdown. I have rough plans I drew up of a Berkut which is similar to a Long EZ but larger, but never got around to building it. I have recently ordered Andy lennons book and plan to get back to designing the Berkut and building an electric version in the near future

cooper998

[canard addict]

Beavrdam, What a great variety you have there. The Delta with open mid section has been on my agenda for some time now. How does it fly? Thanks for showing that, Cooper! Is it full scale? Charles

[cwesh]

Hi Charles,

The construction of my Starliners is all balsa. Simple box structure for the fuse, spars, ribs and sheeting on the wings.

On the Mk IV, I even tried a rhino rudder (pic below). I had it moving a good 45 degrees to each side and all it did was to yaw the nose over about 5 degrees, did not do much of anything, wouldn't even hold the nose up when trying a knife edge. Guess the main fins are too powerful to allow the plane to yaw much.

SEFF 2007, humm......

Later!
Chuck

[magic612]

Here's a picture of my experimental canard plane. I call it the "Half Circle Canard".

Something about canards just look cool to me.

Though my wife did say that this one looks kind of like a lamp shade.

[canard addict]

A Parkzone J3 Cub wing part no. PKZ1120 makes an excellent canard wing. Since we need 120 sq. inches to keep the same COG and the chord is 5.75", cut the wing down to 21 inches or 10.5 each side of the centerline. Take a 3/8" thick piece of balsa and use the tip of the new wing to trace the underside contour for the incidence wedge for mounting, cut the wedge so that the LE of the wing is 0.45" higher than the TE. This will be epoxyed to the fuselage as described before. I added a 1/4" thick balsa cover to each side of the wedge from the underside of the wing to the bottom of the fuselage to sandwich in the wedge and to provide a 7/8 " mount to glue the canard to.See pictures attached. You should reserve six to eight inches of the fuselage behind the canard for battery balancing the model. Plug the elevator servo into the receiver and mount on the servo on the plastic mounts as far forward as the wire will reach. You may need a short extension wire to place the servo further forward and reduce the length of the elevator control spruce stick. The elevators should be 1.75" wide and should run from the wing tiplet to 1" from the fuselage side. To control the elevator, I used a 1/8" sq. spruce stick with a 0.032" wire at the rear with Z bend and drilled it up front for 0.045" wire to pass through. The front wire should be epoxyed onto neutral elevators as close as practical to the end of the elevators for firm control. Needle nose pliars were used bend the horn around the spruce stick. This system has worked well on four models. Add some sharp looking tiplets. Charles

[canard addict]

Cwesh: Rhino rudders have been tried on full size canards but have not been very successful and in at least one case was removed. Your plane with the large wings may be hard to turn, I had the same triangular rudder on the Egret at first and it had little effect. I added a similar triangle behind the first and was amazed at the change. I figured that the airflow from the blunt nose was not passing across the large lower area. Magic, Please keep us up on your interesting work. Charles

[magic612]

Originally Posted by canard addict

Magic, Please keep us up on your interesting work. Charles

Will do! That picture is about version three of that general concept. Now that I have a powerful enough brushless motor to put on it, it should perform better. I am considering shortening the fuselage though, as I think that will help with balance issues. It flies okay, but kind of "hangs down" in back, but I'm not sure if that was the lack of thrust from the brushed system I had on it, or something else. I'm going to try the brushless first, then see if any modification is necessary.

One modification at a any one time seems to be a good rule of thumb - especially when you already know it WILL fly!

[Smash McCrash]

Is there some reason that the canard needs to have positive incidence? I haven't ever built or flown a canard, but I really like the look of them. I wish that Estes still sold the Astro Blaster, although Caveman Rocketry does. But, they are in Europe. Shipping is the killer in this case. EAM was working on one that they called the Nomad RPV that I was really interested in, but they scrapped it.

Mike

[canard addict]

Magic: If the speed increase does not help, you may be tail heavy, If the COG is moved forward, I would add a couple of degrees of positive incidence to the canard wing. The rear is probably hanging down to get it's needed angle of attack for lift. Charles

[canard addict]

Smash: The canard wing must stall first to keep the main wing flying. The canard positive AOA makes sure that the canard lifts the front of the plane before the rear wing does it's part. With increased speed, the canard raises the nose and this gives a positive AOA to the rear wing which then does it's job. If the area of the canard is too small, it will stall as the plane slows during climb out and the nose will drop,causing a gain in speed and the cycle repeats. I have seen this in my maiden flights as the model hops across the field like a rabbit. I found that more power and speed will correct the hop or A bit more area or AOA for the canard will help. The area of the canard is 30% of the wing area on my style of plane and usually 3.5 degree canard incidence works well. I believe that less canard incidence is needed on fast and/or short nosed models. The Long EZ is fast, Has short coupling and seems to have much less canard incidence. The turbulance from the front wing should be less on the LEZ and therefore will disturb the rear wing less. These are just my feelings about what happens and my be right or wrong. We all need to pitch in and help.

[RCSuperPowers]

Wow, this is my kind of thread! Great stuff.

[canard addict]

I used 0.078" piano wire for the nose gear. The straight section is 6.5" long and a light plastic 2" wheel was used. I bent a U shaped section at the top about 1.25" long at 45 degrees from vertical to slide into the fuselage corners. The nose gear helps to balance the model. Charles

[canard addict]

Thanks, RC Super, I also love your planes and videos. Why don't you show us a design or more? Charles

[cooper998]

Looks like a popular topic! already on page 2
Charles, the picture is of the full scale Berkut, I unfortunately just found out that it went out of production and will not supply 3-views or anything concerning the aircraft. I have searched through my research materials and can't find my stuff on the Berkut. I am going to try the full scale Canard forums and see if I can obtain some documentation there.
I plan on scratch building a stand off scale version in order to work out the specifics of CG and retract locations

cooper998

[magic612]

Originally Posted by canard addict

Magic: If the speed increase does not help, you may be tail heavy, If the COG is moved forward, I would add a couple of degrees of positive incidence to the canard wing. The rear is probably hanging down to get it's needed angle of attack for lift. Charles

Thanks for the tip! Much appreciated - this being an experimental design, I had to guess where the CG needed to be, so it's certainly possible that it's tail heavy.

I will try that, though as I said, I like to eliminate one thing at a time. If it's simply airspeed, then the brushless motor will take care of that. If it still "hangs down", then I'll look at COG and possibly adding some more positive incidence to the canards. At present, they're about 5 degrees up.

[canard addict]

I just read from a 2005 thread on my Slow Stick that it has a 1/8 balsa shim on top of the Main wing trailing edge mount which reduces the incidence to one degree positive. I looked and it is still there. I also saw that it has four degrees of canard incidence which results in a three degree decalage.My battery is a seven cell pack of Sanyo 600 AE nicads which give a decent flight with plenty of reserve to land. The GP 1100 nimh are the same size and will give more flight time but cannot be charged in 25 minutes. The white wing stabilizers are six inches wide and 5.5 inches tall and are attached with canopy glue to the top of the second rib crest from the center of the wing. You can be inventive with their shape as long as the area is there. Mine are out of character for the stick design and the round type that are on my Soar Star may look better.BTW, just slide the battery assembly to get the COG right. Charles

[canard addict]

Cooper 998, Too bad you cant' locate the plans. The COG calculator that I referred to has a double paneled wing section that will probably work for you as it did for me on the Long EZ. Charles

[InspectorGadget]

OK Charles,
Here is one for your thread here. I just finished building and maidened a FFF Shinden.
It flew well once I got her trimmed and I can't believe the axial rolls---they are incredible.The GWS M-003 provides plenty of power for the 15oz airframe with the 1350 3S lipo onboard. The steerable nose wheel was a challange, but it works well.
I will attach a few photos from this morning before she flew.
C-YA RL

[canard addict]

Inspector, Hobby Lobby will be upset over your great design. Now that it's trimmed in, Will you add some color to the fuselage? Tell us about the structure, please. Isn't it hollow with internal parts? Will it do an outside loop? mine will do the first half then flips upright. Since mine has gone to three cells, it is much more fun. I will attach the picture with two cells. Charles

[InspectorGadget]

Originally Posted by canard addict

Inspector, Hobby Lobby will be upset over your great design. Now that it's trimmed in, Will you add some color to the fuselage? Tell us about the structure, please. Isn't it hollow with internal parts? Will it do an outside loop? mine will do the first half then flips upright. Since mine has gone to three cells, it is much more fun. I will attach the picture with two cells. Charles

Charles,
Thanks for the compliment, but I hope they don't get too upset.
I plan to paint it soon, but I like to make sure it flys before I spend time on the decorations. I need to decide on what paint scheme I would like.
The fuse is hollow 1.5" inside width, with most components inside. I had to mount the servos part in and part out.
I haven't tried an outside loop, but it will do an inside wiith no problem. And it is a lot of fun to fly.
C-YA RL

[BeavrdamElectric]

Originally Posted by canard addict

Beavrdam, What a great variety you have there. The Delta with open mid section has been on my agenda for some time now. How does it fly? Thanks for showing that, Cooper! Is it full scale? Charles

Thanks! The first flight was about 20' on that one. I fixed the nose, cut down on the aileron throw and moved the CG back a bit. That got a couple wild laps around the field, I need to cut down on the aileron throw some more and fix the nose again. Once I get it flying decently I'll put a second one together, hopefully I can keep that one from acting like a lawn dart. I have the pieces cut out and edged, the second fuse has a full balsa outline.

If the canard doesn't have positive incidence it won't be "loaded", and the CG will need to be farther back. The designs I've seen without incidence don't have movable surfaces on the canard, just elevons. I'm not sure if these qualify as true canards, they're more like a flying wing or a delta with some forward area. It could be fuselage area and function the same.

There are a couple items here about canards;
http://www.djaerotech.com/dj_askjd/askdesign.html

Good Luck!

[canard addict]

RL: I noticed that the front part of the canard on my Shinden was a bit floppy, so a piece of 1/16 by 3/16 spruce was added as a brace. It may pay off in a fast pull up from a dive. You have to look well to see it. It does not interfere with the movement. Charles

[canard addict]

Beaver, That link is awesome! I read it a couple of years ago. I guess intuition and trial and error have guided me through my modeling years. Regarding your thoughts on canard wing behavior: The COG of the Hobby Lobby Shinden is well into the main wing which seemed to take away the action of the tiny 20% canard. The model was sick on two lipos. I added more prop pitch for more speed which helped a bit. I figured the canard needed 6 inches more area to fly slow. I ended up with 3 more sq. inches on the canard, added a cell and moved the COG forward. At higher speed and more load on the canard, It is now much more fun. Charles

[icrashrc]

Sig Tri-Star. Flies on 300+ watt electric or Aerotech 32mm rockets.

Electric setup is a Mega 16/15/5, geared 2/1, 11x8 carbon folder.
4s 1p Polyquest 2200. Went back and checked my log. It's about 360 watts static on a fully charged pack. A 15 second motor run takes it to about 1000'. The plane will thermal well in moderate lift but it's not an all out sailplane.

The rockets... Ya know, sometimes i get these crazy ideas. This plane was one of them. On rocket power it's flying weight is about 8oz. lighter than the electric setup so it does thermal a little better. The TriStar flies very well off the launch rack 90% of the time. It has no movable rudder so if it yaws coming off the rack it can be a handful. That's what you see in the video i linked to. If it yaws you have to roll and pull elevator to compensate. If i had it to do again i would probably add more sweep to the wing to make the vert. stabs more effective. Rockets make 10 lbs of thrust and burn time is 6 seconds. Costs $8usd per motor so it aint cheap!

http://www.rcgroups.com/forums/showthread.php?t=597881

[RickAvery]

I picked up this Multiplex Sonic Liner a few months back after they were discontinued in the USA. Twin brushless, LiPo. Very kick back easy to fly. Looks neat in the air too.
Rick

[canard addict]

Icrashrc, That is a beautiful Tristar and it must really move with 300 watts! I can't believe how well it looks after enduring rocket flights. Can you give us a description or series of events of the rocket flight. I wanted a Tristar but could never find one. Charles

[canard addict]

Rick, You were lucky to find your Sonic Liner, They look awesome against a blue sky. Too bad that Boeing built the Airbus instead.What brushless motors did you use? At the last two Little Rock SMALL meets, four pilots have taken their SL's up for formation flights. They made multiple passes across the field and it was an incredible show. If you love canards, The book by Andy Lennon is a must have. It covers all that were built from the Wright brothers up to 1984. It is by Aviation Publishers,Hummelstown, Pa. with Motorbooks International, Osceola,Wisconsin listed as distributors. I was lucky to find mine on Ebay. Charles

[MustangAce17]

Charles,i was lucky enough to find a Simprop Piaggio Avanti to go along with my Long EZ 380. It should be here soon(hopefully before christmas) but i will start on it as soon as i get it. I'm going to work for a air sampling company testing edf's soon so tomorrow is my last day at the HL craftstore. Should give me the time to build. I plan on dual 28mm brushless and lg,possibly air retracts

[tometech]

This thread is awesome! To much to assimilate all at once. How does the Hobby Lobby Shinden fly?

[canard addict]

Mustang: You have two quick models there! As you know, I have assembled the Long EZ and I dearly love the Avanti with it's three horizontal surfaces. If it had Landing gears, I could not have resisted getting one.I hope to see you again at an event with your planes. Tometech, the Shinden was fun to assemble, and is fun to look at and fly. I do not regret the experience. Mine has the AXI 2204-54 with three lipo 800's and the GWS 7.35 prop. The efficiency is in the 70s and it pulls about 5.3 amps at 57 watts.(91 watts per pound). I added three sq. inches to the elevator (see picture) and moved the cg a bit forward. It is quick and gets good attention at the field. I especially enjoy knowing that only two were built in 1944, they were intended to go after the B29s at 459 mph. We have one in Washington, I believe. Please don't attempt to go with two cells.

[tometech]

Canard Addict: Some of the Canards are built for lift and some are flat. How much difference does it make? Will the Slow Stick canard fly with a flat canard? Does it matter whether the verticle fins are inboard or on the wingtip?

[MustangAce17]

Just got here from work and unpacked the Avanti. Box pic makes it look gorgeous but that's all i can see til christmas.

[canard addict]

Tometech: My Slow Stick canard has a flat bottom canard, the Pico Stick canard has a 1/8" thick flat foam canard, my Soar Star canard has the under cambered Parkzone canard and all fly very well. I find that the flat bottom airfoil is capable of taking my models up in a hurry. I use them on my own designs. I associate them with the Clark Y or scale J3 Cub type. I believe that too much under camber can cause a model to tuck under in a dive. This tuck under has been demonstrated to me with the Wingo and the Firebat. On my Wingo and Soar Star canards, I file the wing bottoms nearly flat. This was done on my stock Wingo and allowed the model to fly flat and fast. The Slow Stick canard is so stable and forgiving that the balance point is not too critical and you could put any of the three types of front wing on it and probably not know the difference. To me, canards are the easiest of all types to design with success. The Pico Stick was simply turned around with the stock parts and the magic angles and COG were applied and it flew perfect.I put the Winglets just where I feel they need to be and have never had an issue with stability. Some canards have a single rudder in the center rear, some like the Vari Viggen have two close in and others are on the wing tips. The fins that are the most rearward from the COG are the best. Some designers sweep the wing trailing edges back to achieve this. If you will build the Slow Stick as described in this thread, you will love it. If anyone wants the Piconard details, I will be glad to give them here. go to www.m-a-e.com and see my Piconard fly. There are two videos there on it.

[cwesh]

On my Starliners, the canards all use an eppler 214 airfoil, set at an incidence angle of 1 degree. (main wing at 0 degrees) I had tried 2 degrees but the elevator response went "dead". It took a large amount of movement to get a reaction from the plane, it flew fine, just seemed stuck at level flight. (CG stayed the same). Guess I could of moved the CG for better response and stayed at 2 degrees, but it was easier to remove the shim I used to alter the incidence angle.

I think I read somewhere that airfoils do not make much difference if the chord is less than 5 inches. (small Reynolds numbers?) On my planes, only the Mk IV has a chord of 5 inches, the rest are less than that, 4" on the Mk III and 3.25" on the Mk V. On these two, the airfoils didn't amount to much, the MK III ended up close to a simple clark y foil, and the Mk V is just about a flat plate. Both of these planes fly the same. The Mk IV at 5" has a good airfoil, a more crisp elevator response and behaves better when the canard stalls, nice nose up and down motion.

Bottom line, I would say if the chord of a canard is less than 5", the airfoil does not matter, only the incidence angle matters, 5" and over, the correct airfoil can improve the handling of the plane. YMMV!

Had my Mk IV out today, almost calm winds 70 degrees, sunny, ah the joys of Texas in winter!

Later!
Chuck...

[canard addict]

Cwesh, Thanks for the interesting discussion on the behavior of your canard wings. Your planes look fast to me and with the small canard areas, the COG must be close to the main wing. The small aspect ratio of the front wings will cause a quicker stall. I wonder if at 2 degrees with high speed the air flow could be breaking away at the top causing a dead spot around the elevator. My Shinden had the COG well into the main wing and the small 20% canard seemed to be just a toy with little effect. It was slow on two cells and I had to hold 1/2 up elevator during the first flight. I confess that I had the COG a bit forward because the calculator disagreed with the instructions. It was almost like it needed elevons. When the power was doubled,more area added to the canard and cog moved forward, the character of the model completely changed. Maybe you should add area by extending the canard center chord forward and make a swept back leading edge,increase the angle to say 2.5 and bring the COG foreward. The swept back LE acts as dihedral. I really know very little about your beautiful ship and just let my mind ramble.Please tell us more.. Charles

[icrashrc]

I went back and edited my post to answer some questions that have been asked.
http://www.rcgroups.com/forums/showp...6&postcount=34

canard addict; I'm not sure what your question is. Ya load the rocket motor, put the plane on the launch rack, press the big red button. :-)
I can take a couple pics of the rear of the plane to show both setups and how they swap out if that's what you want.

[BeavrdamElectric]

ca, could you say a little more about the Firebat? I have one still in the box. I've read a lot about them being overweight/underpowered in stock configuration, and the nose is a bit fragile, but not much about the flight characteristics. What's this tucking under in a dive? That sounds like something I need to know about or make some changes to head off. Do you think I should fill in/sand off (some combination) the undercamber of the canards?

Thanks and Good Luck!

[canard addict]

Icrashrc, Thank you for the video and info. I will check out the glider thread also. Beaverdam, I built two Firebats and totaled both on the first flight. If you use the canard, I suggest a speed 400 geared 2.33 with an 8-4 prop. or even direct drive as comes with the kit.I believe that the Mega 16-15-6 overpowered mine. My friend, after seeing me crash both, left off the canard and put a hot direct drive Aveox on. I would really cook, maybe 80 plus mph. He had his hands full just seeing it. At low throttle, during aerobatics, it would get into a violent flat spin and only recovered about 30% of the time. There was very little or no damage done because it was so flat and slow to come down. My first one was built and set up as instructed. The Mega must have been too heavy and I had to cut foam way forward to install the GP 1100 seven cell pack. When launched, it turned toward some small trees, I gave up then full up and it just mushed and wobbled into the trees without gaining a bit of altitude. On the second one, I sanded off most of the downturn at the bottom rear of the canard. I figured to keep the canard movement low and added exponential. Big mistake because the electronic trim had lots of movement when applied and had no exponential. I added a bit of Up trim and when launched, the model shot way up to say 200 ft. I turned cross wind still climbing then backed off throttle and headed down wind. I fumbled with the down trim until the plane leveled off. I was getting relaxed and very happy at this point. I proceeded down wind and turned left into cross wind then added power and turned UP wind. On that turn, the nose dropped as it picked up speed. I applied a little UP with no change then full throttle. I gave full UP and the model did a rainbow tuck all the way nearly to my feet. It hit at full throttle with full UP straight down. There was a ball of white particles in the air. I Know that the trim killed my UP elevator and if I had throttled back all the way, the plane might have been saved exactly like the Wingo is saved from its tuck. I would not care to try a third one but if I did it would be a delta. There are graphical methods available to find the COG of a delta. If you will do a search for FIREBAT you will find plenty of discussion available and a few success stories.

[icrashrc]

If that's a pic of a Firebat in in post 48 it's no surprise it would flat spin. With the vert. stabs so near the CG they are almost completely ineffective. Most properly designed canards have swept wings with winglets to keep yaw stability. The rest of the flight issues you've described are all related to CG and AOA of the canard. You must have positive incidence in the canard as the canard needs to carry the weight of the nose at all times.

[canard addict]

The Firebat flies well without the canard. I should have had elevons on mine. Charles

[icrashrc]

That doesn't surprise me, without the canard it's a totally different airframe.

[cwesh]

CA,

The area on my canards is 30% of the main wing. The Mk IV has a total of 880 sq in, with 180 of that from the canard. The distance between the leading edge of the main wing and the leading edge of the canard is 29". The CG is at 7" in front of the main wing leading edge.

As to stalls, my birds have a very gental nose drop at minimum speed. The nose will drop about 5 degrees and then return to the pre-stall nose up position, just a gental up and down motion, and as it must, the main wings remain flying with full aileron control. At full up elevator, I can make very steep banked turns without any hint of the main wing stalling, tends to give one a bunch of confidence when goofing off low to the ground!

I find these planes to be stable in all axis. I do have dihedral in the main wing, 1" under each tip. The plane will fly by itself and it will continue to fly in whatever direction I put it in, much like a good pattern plane, which was one of my design goals.

I also find icrashrc's comments about vertical fins that are close to the cg being ineffective, I do not agree at all. I find through flight testing that it is more about having the correct area for the distance aft of the CG, close to the cg, the more area is needed, which is why I have rather large dual fins. I even got to find out what happens to one fin that decides to "self destruct" in the air, was testing out rudders on the Mk IV and had one flutter itself to death. The plane did not seem to care at all that it was flying on one fin, I just flew it around at normal speed and landed just fine, even the engine kept running after it's balsa meal. (Prop chewed up the departed fin)

Also, put together a video of the Mk IV, it was taken last spring by my 8 year old son, he was attempting to use my old camcorder. It is on my web site at this link:

Starliner Mk IV video

The video is 13 megs in size and runs for 3 minutes. It is "not the best" video, but it should give you a hint of how the Mk IV flies.

Later!
Chuck...

[canard addict]

Cwesh, That plane looks to have great response from the canard wing. I figured 25.7% but who cares with those results. I believe that as speed increases,the canard incidence can decrease. My goose weighs 32 ounces, has 3.5 degrees canard incidence and probably does 40 mph tops. Charles

[tometech]

CA-Which flys slower, the PicoStick or the Slow Stick? Does that hold true when they are converted to Canards as well? I really liked the video of the PicoNard with the
brusless motor. It looked very smooth and relaxed.

Tom

[dalbert02]

My Viggen. Built from Burt Rutan plans. Neu ORK power.
-dave

[RickAvery]

Originally Posted by canard addict

Rick, You were lucky to find your Sonic Liner, They look awesome against a blue sky. Too bad that Boeing built the Airbus instead.What brushless motors did you use? At the last two Little Rock SMALL meets, four pilots have taken their SL's up for formation flights. They made multiple passes across the field and it was an incredible show. If you love canards, The book by Andy Lennon is a must have. It covers all that were built from the Wright brothers up to 1984. It is by Aviation Publishers,Hummelstown, Pa. with Motorbooks International, Osceola,Wisconsin listed as distributors. I was lucky to find mine on Ebay. Charles

CA,
My SL has twin warp-4 5 turn motors spinning 6X4 APCe props, two CC TB-18 ESCs & a 2200mah, 3cell, 20c LiPo. Easy throttle will get you 15min of flight. Thanks for the canard info. Have a good holiday!
RIck

[canard addict]

Tom: The Piconard is small, light and must be faster than the ST and with the peppy CD Rom Outrunner, has no problem pulling up from the outside loop.The Slow Stick,with the large draggy wing has to be slower but gives you time to savor each control movement. With the geared 11-8 prop it pulls well through a loop. Depending on my mood, I get a big charge out of both planes. I have not built the standard version but from what I hear, they wouldn't have a chance against the canards in wind. I did hear that the modified Slow Stick was clocked a 80 mph in competition from an RC Groups thread. I believe you said you enjoyed slow and scale like flying and I would suggest the big one for you. With it's longer fuselage, the troops are amazed and I have a good friend who lost a bet by saying it could not fly. Dalbert02, Thanks for the Viggen picture!! Please give us some more stats. You guys have just made my season with your contributions to my thread and I wish to sincerely thank each one of you. Charles

[BeavrdamElectric]

ca, thanks for the words on the Firebat. I can see the problem though, you made it look too good. That'll make 'em crash every time.

dalbert02, nice VariViggen!

Good Luck!

[canard addict]

I put two Trick RC Zagi motors on th SL driven by eight GP 2200 nimh which are 13 ounces. The motors each pull 14 amps and do a wonderful job and will even loop the plane. If someone will tell me where to buy the Saphion 2500 cells, I could replace the pack with three of them and save some weight for an easier launch. When I have to launch it,It sags and I feel that one day it may go in sideways. Any other way to get 9.6 volts under 13 ounces would help. Charles

[Old Fart]

My buddy is flying his SL on twin 2815-3000 Himax, 6x4, CC45's, paralleled 2100/3s. Milady managed to find one for me for XMas, I may go with Mega 3 turns. Looking at Motocalc, I think a 16/15/3, CC45, 5.5x4.75 package on 3S will be a good all around flier - and swapping in a pair of 4S should liven things up

[canard addict]

OF: Terrific that you were lucky enough to get th SL. The Dec. 2004 issue of RC Report has a great informative article by Thomas Young. He and I believe that the model should not exceed three pounds. Also it does lots of compact tricks but must never be put into a long dive because the canard wing will fold. This plane will surely grow on you with time. I know you have seen how your buddy has to give it a big push to launch. That's why I want lighter batteries. Mine is built entirely with canopy glue including on the motors. I also have an air scoop on the top front of the hatch and a carved out air exit at the hatch rear. The motors are also cooled with an extra air scoop on the inside part of the nacelle. Charles

[Old Fart]

I hear you on the airflow - we did that to his after the _first_ flight. I know we put a CF spar down the spine, I'll look tomorrow night to see if he has anything added to the canard (I'll be at his house feeding his dogs, building planes and smoking his cigars while he's on vacation)

1320/4S TP Prolites are pretty lean..