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Old Oct 29, 2007, 02:53 PM
Crazy Heli Technogeek
Kai_Shiden's Avatar
USA, WA, Seattle
Joined Sep 2004
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Kai's Shuriken (profile mid-pusher)

Here's a new profile plane that I've been tinkering with, the templates are being worked on. I figure it's about time that I started a thread on it here at RCG (already have a thread on it at Wattflyer).

http://www.nwheli.com/Videos/Planes/...10-25-07sm.wmv (30MB, Right click, save-target-as)
Shuriken Indoors (5 min 42 sec)


http://www.nwheli.com/Videos/Planes/...n_10-28-07.wmv (24MB, Right click, save-target-as)
Kai's Shuriken at the park (5 min 49 sec)

-Kai

P.S. Both videos are the exact same setup: LittleScreamers Parkjet, PHX-25, AR6100, APC6x5.5, 3s TP1320 (it's really a bit too quick for indoors, but the Shuriken can maneuver so tight that it just means the majority of the flight is under 1/2 throttle indoors).

Edit: Plans are now available for download: http://www.nwheli.com/Plans/Shuriken.pdf (full sheet currently, tiles may be available later)
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Old Oct 29, 2007, 03:31 PM
Crash & Burn
rmgmag's Avatar
Glastonbury, CT
Joined Nov 2004
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Very cool! Do you have plans?
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Old Oct 29, 2007, 03:41 PM
Crazy Heli Technogeek
Kai_Shiden's Avatar
USA, WA, Seattle
Joined Sep 2004
4,205 Posts
Quote:
Originally Posted by rmgmag
Very cool! Do you have plans?
I've loaned the plane to a friend and he's making DWG and PDF versions of the templates. I'll repost the two post testflight reports I made over at Wattflyer here:
Quote:
Originally Posted by From 10/13/07
WooHoo!!!

The test flights went great today, results are that it's very neutral at all speeds and orientations, but really needs some rudders to give it smoother coordinated turns.

I was lazy and didn't bother cutting and hooking up the rudders for today, but yet, even without the rudders it will already almost knife edge . I could cut down the nose a bit to get it to work as an elevon only plane (basically cutting surface area from the vertical height of the nose would change the knife edge CL aft a bit and make the tail follow the nose "weathervaneing" in yaw), but I would rather have full controls and keep it as neutral in all axis as it is now.

I was kind of blown away that it was easily able to do rolling circles and slow rolls even without the rudders . It even slows down very nicely, but could use rudders to give it more control at slow speeds.

All is not perfect though, as I think I might have one of the vertical stabs slightly out of alignment , it turns easier to the right than to the left. But adding in the rudders will also solve that. Basically in slow left bank turns right now the tail tends to slide down into the turn (and it just flys on dog walking sideways until you throttle up enough to pull it back in line, did I mention that it's almost rediculously neutral , more like a 3D plane than a foamy jet ).

I'm going to add the rudders to it tonight and hopefully get some video of it in flight soon, I'm confident that it's going to blow away my old SU-37 in all flight regimes, especially when it comes to knife edge, I could never get my SU-37 to knife edge at low speeds, where I'm confident this one will be able to knife edge at 1/2 throttle.

Today went so well, that I even managed to find a perfectly neutral CG that allows it to fly inverted without any elevator , and without anything other than battery placement.

-Kai
Quote:
Originally Posted by From 10/14/07
I made it out the the park late today (didn't add the rudders until this morning).

The flight report is, that the rudders were exactly what it needed, now even with a perfectly neutral CG, it glides excellent (it does require some rudder corrections in glide, but it only slowly yaws out on it's own, so it's very easy to maintain yaw stability). At the field I wanted just a little bit more pitch stability, so I added about 3/4" of depron to the back edges of the tailerons, and to achieve a smigeon more yaw stability I also shaved the nose height down by about 1/16th" top and bottom. While at the field I also sanded all the leading edges round.

With those changes, it now knife edges like a 3D foamy, it only takes 1/2 throttle and a hair of rudder to maintain knife edge level flight (and can even do knife edge harrier ). Rolling circles are painless and easy with just adding some elevator timing in the rolls. Glide requires the mentioned yaw corrections and a slight amount of forward pressure on the elevator (not even so much as to feel the stick move ). It can do elevator falls, tumbles, flat spins, snap rolls, flat turns, harriers, and any other maneuver I can throw at it (ie, I myself haven't mastered rolling harrier circles, and just like any other depron foamy, it doesn't have enough mass/inertia to pull off a lomcevak ), and the great part is, it does them all equally well inverted as it does upright .

Even with the CG set dead neutral (not nose heavy or tail heavy), it really locks in and tracks true at high speeds. I was pretty amazed that it's only "bad" habit is a slight tendency to drift in yaw at low speeds, it's speed range is incredible, I even pulled off some hovers with it today. It does have a tendency to wing rock slightly at over 60deg high alpha (which does make hovers harder to maintain than with a 3D foamy), but it takes some pretty extreme angles before that tendency shows up. With the LittleScreamers ParkJet, TP1320, and PHX-25, it will fly level at 1/4 throttle, and very visibly accelerates when the throttle is opened up, it has unlimited vertical and hovers around 60% throttle, and has very good top speed (faster than my SU, but by how much, I don't really know, I would guess that it does around 60mph, not quite as much as I wanted, but I'm not willing to sacrifice the "fun to fly" factor I get out of it right now by trying out other power systems).

As to posting the design online, I used to make plans, but found them to be a royal pain in the neck to make to my own satisfaction (tiled and full sheet, plus all the print testing to make sure they scale right, and optimizing foam cutting layout, on my SU-37 plans doing all of that took hours upon hours).

I'm making up templates now that the shape is all refined, and will be lending them to local flyers who want a Shuriken (that's what I've decided to name it, a Hira-Shuriken is a throwing star, and when it pulls into vertical it looks like a 5 point star). For those who want one online, I'm going to take pictures of it from all angles and overlay the measurements.

With any luck, someone else will like the design enough to draw up plans, personally, I have so many projects in the fire that I don't have the time to spare (that's what comes with flying both planes and helis, and being available to help people with their helis, spare time to do all the projects I want comes at a premium ).

-Kai

P.S. Extending the tailerons back that 3/4" also removed any flutter they had, I can now do a full throttle dive and it just runs dead true (the ground comes up scary fast though ).
I left out all the smiley's, as I'm at work right now. Here's the thread over at Wattflyer: http://www.wattflyer.com/forums/showthread.php?t=25367

-Kai
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Old Oct 29, 2007, 03:59 PM
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shockflyer12345's Avatar
United States, MD
Joined Nov 2004
468 Posts
Cool plane Kai!
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Old Oct 29, 2007, 04:05 PM
Sussex, UK
RobinBennett's Avatar
Crawley, West Sussex, UK
Joined Jun 2004
7,376 Posts
Cool!

No canards and rudders only above the wing - did you not think they were necessary?

Is the prop at the rear of the slot for a reason?

Are those elevon extensions?

Have you tried with just elevons, and no ailerons?
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Old Oct 29, 2007, 04:31 PM
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USA, WA, Seattle
Joined Sep 2004
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Thanks guys, it's a darn fun plane (and has a very neat look in the air if I do say so myself ). I named it the Shuriken after noticing that it looks like a 5 point star in the air (Hira-Shuriken is a throwing star).

No canards to reduce drag, rudders only above the wing because it's easiest to hook up the rudder linkages and hinging that way . Prop at the rear of the slot in a feeble attempt to cut down prop noise (then I rigidly clamped the motor to the CF wingspar, so it ended up ampliflying the motor noise anyways ).

Yup, the elevons seemed to need a little bit more size for rigidity and to center up knife edge to conventional CL (I shaved the vertical nose and added some material to the elevons to center the horizontal and vertical CL positions). On the upside the extra material on the elevons removed any flutter that it had (before the extensions the tips of the elevons were too thin and fluttered in high speed dives).

It would probably work fine with just elevons, but I like the extra roll rate and stall characteristics of having the tailerons and ailevons linked

The rudders are long but short height to make them rigid against flutter (this also reduces the yaw to roll interaction), the ailevons start a little ways out from the fuse (to allow more linkage clearance and to strengthen the airframe around the prop slot), and there are many other design elements that allow it to have a very wide speed range. The only carbon on the test plane is the single wingspar and the push/pull linkages.

With the LS ParkJet, 6x5.5, and 3s TP1320, the Shuriken will literally fly level at a little less than 1/4 throttle . I think for indoor/outdoor in small areas, a LS Purpile Peril would allow more flight time and be easier on packs with a tolerable reduction in max speed.

-Kai
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Old Oct 29, 2007, 04:41 PM
Starting to Rebuild
Wingnut31's Avatar
Fayetteville NC
Joined Jun 2006
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Looks great. I can't wait for some plans.
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Old Oct 29, 2007, 04:55 PM
Crazy Heli Technogeek
Kai_Shiden's Avatar
USA, WA, Seattle
Joined Sep 2004
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Thanks Wingnut31,

Plans shouldn't be too far off now that I've loaned the plane to someone with the time and software resources to draw it up in CAD (the last plane design I shared I drew up in MilkShape3D which is a game object designing program, it was painfull drawing each vector one by one ).

I went and added more static pictures to the first post, here are a few pictures of it on it's first test day (before I hooked up the rudders and extended the elevons). Thanks goes to Kosh for running the camera outdoors (both for the pictures in this post and for the outdoors video above).

-Kai
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Old Oct 29, 2007, 05:11 PM
Crash & Burn
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Glastonbury, CT
Joined Nov 2004
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Is it Depron?
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Old Oct 29, 2007, 05:26 PM
Crazy Heli Technogeek
Kai_Shiden's Avatar
USA, WA, Seattle
Joined Sep 2004
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Yup, 6mm depron. Mine came out a bit heavy as I was in a rush to build it (had broken the back of my year old SU-37 and needed a new jet). With 3s TP1320, 9gr servos (because they were cheap ), and reinforced strapping tape hinging (it was what I had around ), it comes out to 10.2oz AUW.

The raw airframe with just depron, hinging, UHU glue, and CF spar it came out to 3.3oz (so there is a bunch of room to improve AUW considerably).

-Kai
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Old Oct 29, 2007, 05:27 PM
He Did WHAT? "AGAIN?"
Kosh28's Avatar
Seattle
Joined Nov 2004
293 Posts
The plane is all Depron and I was lucky enough to test fly this yesterday. The handling is simply astounding and I watched Kai pull off a few perfect vertical hovers even. Cant wait for my own.
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Old Oct 29, 2007, 06:03 PM
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Joined Jan 2007
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Quote:
Originally Posted by rmgmag
Very cool! Do you have plans?
From the scale of the deck planks (appear to be 2"x4" (nominal) with 1/4" spacing) and the two feet in the overhead shot, the wingspan looks to be about 24". A nice set of templates could be made from the top and side view. I can create and add scaled and tiled templates here, if anyone can't wait for the (official) plans.

Cheers,
Bill Segraves
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Old Oct 29, 2007, 06:22 PM
Crazy Heli Technogeek
Kai_Shiden's Avatar
USA, WA, Seattle
Joined Sep 2004
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These pics might help out, and some dimensions from the other thread
Quote:
Originally Posted by Kai_Shiden on WattFlyer
From nose to the inner LE of the wings is 13inch, from nose to the spar is 22", wingspan is 22", frame separation is 6.5". The dimensions of this plane are pretty critical (to get the handling characteristics I wanted, I had to add about 15mm to the tailerons, and shaved about 1.5mm of height off of the top and bottom of the nose).

If built for use without rudders, the lower side frames should be extended downward and vertical stabs made taller (those two changes would give it yaw stability, right now it's setup on the borderline edge of yaw stability which is why mine doesn't work that great without rudders).
CG is 4.5" in front of the spar (or 4.5" behind the wing to nose joint), I suggest starting a bit ahead on CG and working back. The recommended CG is dead neutral (no elevator upright or inverted), but may make the pitch feel too extreme for many people .

-Kai
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Old Oct 29, 2007, 07:01 PM
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Scaled Photos Are Not Plans!

Quote:
Originally Posted by Kai_Shiden
These pics might help out, and some dimensions from the other thread
CG is 4.5" in front of the spar (or 4.5" behind the wing to nose joint), I suggest starting a bit ahead on CG and working back. The recommended CG is dead neutral (no elevator upright or inverted), but may make the pitch feel too extreme for many people .

-Kai
Thanks, Kai. After I posted 24" WS estimate, I realized you had stated the size of the prop. From, 6" diameter of the prop, I calculated 21.15" WS from pic img_0549.jpg.

Now, with 22" WS, I can do a more accurate scaleup -- doing it now. O.K. Done. See PDFs below (Tested: adding the WS segments from three of the tiles gives 22-1/6" WS, about as close as you can get from a JPEG, measured from a screen image with 1 pixel resolution, and then scaled at about 2.5x).

[Edit: Note to readers: The scaled images below are not plans. See Codesource plans in a later message.]
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Old Oct 29, 2007, 07:03 PM
Starting to Rebuild
Wingnut31's Avatar
Fayetteville NC
Joined Jun 2006
1,028 Posts
Can you buddy produce a size that could handle a six series 2000kv motor and a 2070 mha 3s Lipo? Im guessing around 33" Ws.
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