Jetpainter
640cc Uber Pimp
I agree, it's neat to see something totally different that no one else is doing.
Scale Curtiss XP-55 Ascender
- Thread starter Larry B
- Start date
Larry B
70cc twin V2
Thank you guys, there is a reason that no one else is doing something like this! Remember this is model #2
The Ascender is a very strange type of airplane, at first glance it looks like a standard canard but it is not really a canard at all. Curtiss designed the thing as a true flying wing with a full floating elevator surface out in front giving the airplane a "canard" appearance.
As we all know it is impossible to adapt this type of set-up to a R/C model because our control surfaces have to be firmly attached to a servo via some sort of linkage, we can't have a full floating surface as Curtiss did. The full scale airplane had a "false feel" control system for the pilot to help control the elevator, the real plane had control throws that would put your 3D models to shame! (Check out the control throws on the video)
What I am trying to do is adapt the design to a canard where the forward surface will actually develop some lift in addition to being the elevator where as the full scale elevator did not develop any lift at all, it only controlled the pitch of the airplane.
Now what is difficult is that when I make the forward surface a true canard now the CG must be moved forward and when you do this the main gear must also be moved forward a bit or you end up with to much weight on the nose and the model will be difficult to rotate on takeoff.
Did I confuse everybody?
The subject has several other issues that make it a challenge, maybe that's why smart modelers leave it alone?
Larry B
The Ascender is a very strange type of airplane, at first glance it looks like a standard canard but it is not really a canard at all. Curtiss designed the thing as a true flying wing with a full floating elevator surface out in front giving the airplane a "canard" appearance.
As we all know it is impossible to adapt this type of set-up to a R/C model because our control surfaces have to be firmly attached to a servo via some sort of linkage, we can't have a full floating surface as Curtiss did. The full scale airplane had a "false feel" control system for the pilot to help control the elevator, the real plane had control throws that would put your 3D models to shame! (Check out the control throws on the video)
What I am trying to do is adapt the design to a canard where the forward surface will actually develop some lift in addition to being the elevator where as the full scale elevator did not develop any lift at all, it only controlled the pitch of the airplane.
Now what is difficult is that when I make the forward surface a true canard now the CG must be moved forward and when you do this the main gear must also be moved forward a bit or you end up with to much weight on the nose and the model will be difficult to rotate on takeoff.
Did I confuse everybody?
The subject has several other issues that make it a challenge, maybe that's why smart modelers leave it alone?
Larry B
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Larry B
70cc twin V2
Getting more stuff done; All the formers in the fuse are glassed in just to add a bit of strength. The canard bearing bulkhead is also glassed in the nose. I cut out the holes for the canard torque tube fairings, they still need just a bit of final fitting but for now their good. Also mounted the motor & spinner just for a trial fit, and the nose gear to make sure everything is going to clear.
Now it's time to start on the wings, my CNC hot wired cores came in yesterday from Coby @ FlyingFoam.com, he does great work and keeps my stuff in his CNC computer files so if I want to build another one or sell a kit he can hook me up.
Now back to the shop!
Now it's time to start on the wings, my CNC hot wired cores came in yesterday from Coby @ FlyingFoam.com, he does great work and keeps my stuff in his CNC computer files so if I want to build another one or sell a kit he can hook me up.
Now back to the shop!
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Larry B
70cc twin V2
As usual I am very happy with Coby's work with his CNC hot wire. Today I determined where I wanted to place the main gear then placed my hot wire template and cut out for my two plywood gear mount ribs. The scrap foam parts are then used as a perfect template to make the ply ribs for mounting the gear plate to.
As you can see I have moved the main gear way forward toward the CG to help the thing rotate better, it will cost in the static judging points but then if it doesn't fly it wont matter anyway
As you can see I have moved the main gear way forward toward the CG to help the thing rotate better, it will cost in the static judging points but then if it doesn't fly it wont matter anyway
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Jetpainter
640cc Uber Pimp
Thanks for posting the link to the Flyingfoam.com. That could come in handy for some of the scratch build projects that are rolling around in my head.
Larry B
70cc twin V2
You are very welcome JetPainter, Coby is kinda in the middle of a move so he may be hard to get ahold of. His #1 shop help took another job so right now he is also swamped with work, but he is worth the wait for some good CNC hot wire work.
Speaking of hot-wire work I have been cutting up my wing cores. Both the gear mounts are done and both the aileron servo pockets are all done. The swept wing sections are ready for sheeting, I still have to hot-wire the wheel wells in the center section.
Larry B
Speaking of hot-wire work I have been cutting up my wing cores. Both the gear mounts are done and both the aileron servo pockets are all done. The swept wing sections are ready for sheeting, I still have to hot-wire the wheel wells in the center section.
Larry B
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Larry B
70cc twin V2
Lots more done today, last night I sheeted the first foam core of the swept wing panel, I now have the leading edge taped to the core so that will be all cured tomorrow. Today I sheeted the second panel, it's now setting with about 500 lbs on it until tomorrow. Also got the center section ready to sheet, I used 1/4 ply to carry the wing dowel loads, one piece in the wheel well and one on the leading edge.
