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General control line discussion => Open Forum => Topic started by: PJ Rowland on May 06, 2017, 02:33:57 AM
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Ive been busy since I completed the drawings in December . This is my own design with collaboration of a few minds to attempt to get a new C/L design competition spec Biplane for todays engines.
This was built for PA. 75 Current weight is 65.7 with all hardware.
Wing area is based around certain wing loading for a projected weight of 75oz. Glad I came well under that but there were lots of unknown elements.
Lost foam wings
Foam Stab sheeted in 32nd
Foam / Carbon Flaps Balsa.
Top fron front to rear is molded shell.
Finished in carbon veil / Auto paint.
Clear will be PPG in a few days.
The control system is designed for this plane specific.
Basics.. Bellcrank. Rear idler arm driving flaps with a counterdrive system for reduced friction. Has dual Walker Flap devices.
This will be my 2017 Nats plane and I have also put my US number on it and confirmed it fits in my travel box.
(https://preview.ibb.co/g35HFk/IMG20170416155943.jpg) (https://ibb.co/ejCxFk)
(https://preview.ibb.co/f1nHgQ/IMG20170506165238.jpg) (https://ibb.co/hLgcgQ)
(https://preview.ibb.co/mbfsFk/IMG20170506165251.jpg) (https://ibb.co/n0XTo5)
(https://preview.ibb.co/dYghFk/IMG20170506165221.jpg) (https://ibb.co/fxYJo5)
(https://preview.ibb.co/i3WhFk/IMG20170506165046.jpg) (https://ibb.co/frcdo5)
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Very Cool! #^
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Congrats on such a unique ship. Looks great! I hope she flies well.Cheers,PhillySkip
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What a great model, PJ. This is really exciting, and I am very much looking forward to your flight reports. Great work!!! I hope the gap proves sufficient.
SK
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Way cool PJ! Best of luck with it!
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PJ
Great looking bipe there H^^ H^^
Reminds me of the F3A bipes in use today.
I know those are great flyers and by the looks of it,so will yours.
Please keep us posted on the flights.
Carl
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Awesome, Dude!
Hey, if I pay for the hotel room will you spend five days or a week in Foster City and build me one just like it? You built that in about the time it takes me to scratch my head while contemplating my navel.
Ted
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PJ, she you are thinking out side the box. Very unusual looking with a lot of RC influence. Hope it flies well for you. H^^
Now Ted the kid, who would fly it for you as I know you are getting a little long in tooth, as the saying goes. LL~ LL~ LL~
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Incredible PJ!
I'm glad we have brilliant pioneers like you to show us all the way.
'Course my friend Jim Hoffman said a long time ago, and I agree with him, pioneers are the guys that get arrows in their heads so the rest of us don't have to!
Best of luck on this one. Only worry I would have is the wing separation thing!
Randy Cuberly
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Another innovative PJ plane. Very nice. Very pretty.
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PJ,
I agree with everybody, the model is simply outstanding.
I would liked to have seen it go together bit by bit.
Do you have construction photos you can Post?
CB
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Thankyou everyone for the kind wirds. It needs to be flown to answer questions I HAVE.. so time will tell.
Ted.. you I dont see myself in your class. I simply look up to the greats such as yourself.. Any previous Nats winners provide inspiration for me to reach that goal. Until find my own way to get this done I will keepbtrying new ideas..
Remember Im building upon ideas all these greats developed.
I didnt take a whole lot of in progress photos. I had no intention of publishing it until I refined the design. Then id do a build guide of sorts.
Its hard to build and photo as your doing it.. when I finish im usually done and want to go to bed.
I had things that were redone and revised. Control systembfor example went through 6 versions before this was finalised!
Here are the fewbi have.. It went together quite quickly.
Dec; plans finalised
Jan; Pre planning and testing
Feb building components
March construction and Assembly
April Finishing stage
May paint.
The guy in the pic is my amazing dad. Its his workshop I build out of and use his help with some elements. 2 pairs of hands and brains can solve alot. Unfortunately his eyes are shot and he just cant see anything up close.
He also has lots of old school building knowledge but doesnt go online or compete anymore. Hebsaid the otherday " I learnrt more watching you do this than I have in the last 20 years"
I just like showing him lighter.. quickerbways to build. using modern stuff.. makes me happy coz he taught me everything I know.. but most importantly taught me how to think for myself.
(https://preview.ibb.co/j89do5/IMG20170408164221.jpg) (https://ibb.co/ebMDMQ)
(https://preview.ibb.co/gXHngQ/IMG20170408164153.jpg) (https://ibb.co/mQUNFk)
(https://preview.ibb.co/i0UuT5/IMG20170406165013.jpg) (https://ibb.co/eX9uT5)
(https://preview.ibb.co/dS4pvk/IMG20170402131640.jpg) (https://ibb.co/eanngQ)
(https://preview.ibb.co/kqCCgQ/IMG20170222142747.jpg) (https://ibb.co/mOok1Q)
(https://preview.ibb.co/dFQCFk/IMG20170319154635.jpg) (https://ibb.co/fwjiMQ)
(https://preview.ibb.co/iHK3o5/IMG20170412140800.jpg) (https://ibb.co/h09Q1Q)
(https://preview.ibb.co/dfR51Q/IMG20170423163456.jpg) (https://ibb.co/igNdMQ)
svg image hosting (https://imgbb.com/)
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VERY COOL PJ, I'd been wondering where you had disappeared to. Best of luck with the new bipe!
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THere is a lot of details here that escape casual inspection, I have been watching PJ work through it, lots of problem solving involved. Hopefully this first will prove a valid prototype at the very least..
As a confirmed biplane junkie, I await test flights eagerly,,
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Two words "IN SANE"!! Nice workmanship and a wild imagination. I hope it flies well!
Don
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PJ,
Your paint scheme is striking and beautiful, nice choice of colors.
Looks like you used sheeted foam for the stab and elevator but the wings are built up?
Reminds me of my R/C pattern days. We didn't hollow the foam back then as I see CL builders will sometimes hollow the thicker wings.
I see you opted for a bit thinner wings. Wingspan?
Here's a photo you might find interesting. This CL model was designed and built in 2012. It's all foam construction.
Were you tempted to go "Take Apart" with your design?
CB
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OK, this is way cool. Way to go PJ! Nice to see you pushing the envelope.
George
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Really a neat design !!!!
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PJ,
Congrats on breaking the mold! Good looking too!
We found on the BiSlobs that they flew better without stagger, (turned different inside and outside) but they had an entirely difference purpose but they don't have the trim devices .
I am anxious to see the flight reports.
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Stab is foam core.
Wings are builtup.
All sheeting in 32nd.
Wings were 134g each...
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Great looking airplane. I am partial to airplanes with more than one wing. I commend you for thinking outside the box.
Pat
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Very nice indeed, PJ. Aerodynamically, it looks about how I would have done it - pretty thin wings, pretty high aspect ratio, and the tail comes out looking disproportionately large even though it isn't.
Brett
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21st century Floh !?
(http://i.imgur.com/ZXWWUAu.jpg)
Tempted to do say a 48 in span one of these , If I wanted to squander wood .
(http://lh4.ggpht.com/_xu-KnS42mro/S9BcGMTDSNI/AAAAAAAAAEk/nl2CKMaH38c/s1600/final10.JPG)
after a Centurie . As in its got Fuse mounted wings , etc . Looks fishey to me, as in Fish Like .
Await flight reports , obviously looks clean & low drag . well Done .
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That's actually a scale model a real aircraft and it looks very well done. H^^
CB
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I can forsee plenty of stability issues if you tried to compete with it..
Short and stumpy dont have good stability in pitch.
Might be fine if it only had a fox 35.
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PJ,
What is the span of your Double Take.
Great name BTW.
CB
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Wingspan is 49" or thereabouts...
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Wingspan is 49" or thereabouts...
PJ,
Thank you for that.
I think your Double Take design is exceptional. Obviously much thought went into the design.
Not as easy to paint as a model with only one wing. That's for sure.
The finish looks flawless. H^^
CB
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PJ,
What's the total wing area?
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Wing area. Im not 100% certain.
Its enough I hope.
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Spent the last few days prepping it for the season. At this stage first flights will be next weekend.
Official weight came in at 1940g or 68.5 oz
(https://preview.ibb.co/btOFMQ/IMG20170513100100.jpg) (https://ibb.co/gAkjFk)
(https://preview.ibb.co/mOTMvk/IMG20170513100008.jpg) (https://ibb.co/nAm8ak)
(https://preview.ibb.co/eg8X1Q/IMG20170513100018.jpg) (https://ibb.co/fraC1Q)
(https://preview.ibb.co/jau0o5/IMG20170513095934.jpg) (https://ibb.co/cXFjFk)
(https://preview.ibb.co/kzFegQ/IMG20170513095928.jpg) (https://ibb.co/cXioak)
(https://preview.ibb.co/fX7Lo5/IMG20170513095714.jpg) (https://ibb.co/ezXmT5)
image hostings (https://imgbb.com/)
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PJ my hat is off to you.
So many of us in the past had thought about leaving "The Box" but never even detailed the conception.
You sir have executed something that is way over the top and I truly wish you all the success in the World.
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PJ my hat is off to you.
So many of us in the past had thought about leaving "The Box" but never even detailed the conception.
You sir have executed something that is way over the top and I truly wish you all the success in the World.
Les,
I agree.
PJ's "Double Take" is absolutely the finest looking and most original design I've ever seen since I've been on the Forum.
Interesting thing is, the "Double Take" doesn't look like it was copied from any other design.
Original and "Outstanding!" H^^ H^^ H^^
CB
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What is distance from fuse center to Lead Out guide ? The bipes I have flown have reduced yaw stability and get squirrely in winds. Always felt it was because of shorter arm with LO guide inboard of wingtips, which are already less span than monoplane.
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Thankyou Les.
That meant alot. You were too busy winning to consider anything different. rest assured your passion, enthusiasm and professionalism are the foundations many of us attempt to use to keep moving forward.
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It wasnt copied from anything correct.
It was a ground up design. No previous information really helped from old research. Lots of fundamentals but hard to make it relevant. Think of having a problem with your Ipad but readsing a help guide written in 1945...
One of the design parameters was everything on it had to be functional.. purposeful stylised aerodynamics and built to do one job only.. whatever the end result of this functionality would yeild would be the final product.
I have not flown it yet .. so I cannot confirm if it has roll stability issues. I had a number of potential issues that needed to be addressed during the design phase. We do know more about Bipe tech than ever before.
For example one of the papers I read was published in 2015 and was a thesis phd paper on the effects of wing gap and stagger for increasing lift. They went through a few hundred iterations and the results were plotted graphed and the c/l were compared.
Obviously this is only semi helpful if you know what your looking to achieve.
I could completely wrong in my approach.. it may fly poorly with issues inverted.. roll stability issues.. tracking issues and weight.. cg location.. wing sections and overall design parameters !
however.. I know a lot of problems have solutions. If you think about any problem for long enough and come at it from each angle the results should be consistent with progress.
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No negative incidence on the TOP wing.
Update.
Ive finally completed the last Final items included control calibration.. which was quite tricky.
Imagine adjusting your mirror in your car.. but each time you do it, the seat. moves.. Then you adjust the seat and the Left mirror moves!
I have carbon calibration sticks which were very useful for this task. All throw.. throw angles were set to neutral. As best as I was able.
Leadout position ,tip weight sealed the hingelines... and the hingelines... and the hingelines.. and the hingelines..
Vortex Generators have been installed in the new 2018 configuration.
Double Take.. Take Double time!
Its comical now working on it.. you finish a segment and you just need focus to repeat the process 4 times identical in some cases.
Again I had unexplainable weight gain. I had all the parts in 1 spot.. The plane completed in another spot. Both had weights verified by scales.
However add those numbers together.. and then weoght the plane with those parts finished...
Somewhere I have gained 21 grams that is unaccounted for. Fuel tubing? Hinge tape and VGs glue for the hinges.. Im not sure but I made efforts to document what went where.. so in the unfortunate event I decide to build another I could use that data to attempt to lower or control future weights.
Very pleased with the Final weight Ready to fly 68.43 oz / 1940g
Now for the Final Wait... some decent weather.. and holidays in a few weeks.
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Ohh my..
Now I might have to build more..
(https://preview.ibb.co/kz7bfk/IMG20170516185008.jpg) (https://ibb.co/cXajY5)
upload your photos online (https://imgbb.com/)
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Ohh my..
Now I might have to build more..
(https://preview.ibb.co/kz7bfk/IMG20170516185008.jpg) (https://ibb.co/cXajY5)
upload your photos online (https://imgbb.com/)
Ok PJ, now you got me! How did it fly?????????????????
I to am a lover of biplanes! y1
OBTW; it a great looking ship!
Jerry
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I am hoping for video.....................
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Ohh my..
Now I might have to build more..
And the impression was...? #^
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Hi PJ,
Great project and gorgeous colour scheme. I agree....a video would be great!
Just a question please. That weight of 68.43 oz./1940 grams, is that empty? With the usual amount of fuel for a big tuned pipe engine like at least 150 cc, this would push the overall weight to over 2 kg. That would give you a nice workout! I guess that the Lancaster was even more "fun"! y1
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This is dry weight correct.
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Having flown my Trivial for several years at 73 oz I can truly verify that it is one heck of a workout, especially in the wind. I also flew Fast Rat for a number of years (many years ago), and the pattern in a 10 mph wind with a 73 oz airplane compares favorably (or unfavorably) to that for a workout. I once heard a great description of that for those that haven't done it...Pick up a 40 lb tool box and jog in place with it for 4 1/2 minutes (or 6 minutes for the stunter).
Be sure you have a hankie to wipe off the sweat! LL~ LL~ LL~ LL~
Randy Cuberly
PS: If you weigh less than 150 lbs (yes I know not many of us old guys do) better get someone to hold on to your belt downwind. y1 <=
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PJ my hat is off to you.
So many of us in the past had thought about leaving "The Box" but never even detailed the conception.
You sir have executed something that is way over the top and I truly wish you all the success in the World.
Of course not everybodys airframe stayed between the lines.
Paul Walkers incredible B-17 and some of the super successful creations from Al Rabe come to mind.
There certainly have been others like the ultra high aspect ratio electric structure that Dennis Adamisin built a few years back.
PJ, it seems as though you've done something special here and have joined a pretty elite group----------now, if you can make it fly well!!!!!!
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My 73 ounce Rabe Bearcat with ST60 flew quite well in high wind. It did not pull any harder than in calm weather. I went to the field Huntersville,to work on motor run problems and it got very windy but I kept flying to the point my plane was being pushed side ways on the ground. The only spot I got nervous was the vertical eights.
I found it did not wind up as bad as my lighter planes. May be the big fat body helped held it back. Not my big fat body the Bearcat big fat body. VD~
I have had some 65 ounces ST60 planes almost pull me over.
Any one who has flown in the wind at Huntersville knows what I am talking about. Very nasty winds ~^
Ed
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Thabks eveyone.
At 68 Its not heavy. Its a modern ship for a modern engine.
I have lots of data from a host of planes and I know with some level of certainty what the wing loading needs to be for stunt. This has a few extras that bump the weight up from your traditional 42 oz fox 35..
The plan is to do more flying over the next few days. I have video but wont be posting this until after its in good comp trim.
Thanks les. I need to make to work. This is and has been my goal since day 1.
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Surely you could put some up of it cutting a few ' 8 's or somesuch . Dont keep us all in suspense .
.Pick up a 40 lb tool box and jog in place with it for 4 1/2 minutes
That'd be like jogging with crates of milk ( 20 pints imperial ! ) at times three . Thou it wasnt yeterday . LL~
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I will post videos. Just this wont happen until its in trim and performance is established.(https://preview.ibb.co/hsWk8F/IMG20170519020702.jpg) (https://ibb.co/fLvCoF)
(https://preview.ibb.co/ckQqav/IMG20170520125713.jpg) (https://ibb.co/mXq1ha)
(https://preview.ibb.co/mzC8TF/IMG20170520101650.jpg) (https://ibb.co/cEWfav)
upload pictures (https://imgbb.com/)
https://youtu.be/yUeKB7NVO0o
Decided to repaint the wheels anyway...
Today was too windy to fly so we just played around for 10 minutes.
This is a very short video of the maiden.
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Noticed you comment on chickens crossing roads...
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(https://preview.ibb.co/mzC8TF/IMG20170520101650.jpg)
New Pilot under training , time to dig out the Cox .020 peewee . S?P