Large "C-3" FTFoam scratch-built cargo plane.

EndeavorRC

Member
Yep, and any info you have on placements of the spars. I was assuming they were placed up on their sides where the screws are on the wing joiner?
Here ya go, maybe this crude drawing will help..
sidewithwing.jpg
wing1plan.jpg
wing1.jpg
wingcut.jpg
 

b-29er

Well-known member
Just FYI, i'm gonna scale this one up for FFE to 200% Looks neat and might be fun to see in combat. Because i'm starting from scratch 1mo out, I'm going to hold on designing the standard 84" for a minute since a lot of the areas that I need to work on don't align with the design in standard scale. I'm offering what i've done so far if anyone wants a jumping off point to design off. Alternatively, i'll be scaling down what I have after FFE to complete 84" plans. So far, here's what needs to be completed:

-Battery bay needs design, fuselage needs slotting to raise the battery bay to a usable height so retracts can fit under (optional).
-the wing and its mating system
-retract bay under the engine pods. I'm assuming a piece of plywood is either cut into the foam in the engine bay or doubled so the retracts have a means to push into the spar.
-fit an finish/servo placements.
-nosecone- Profile is there. Canopy needs to be grabbed off the sea duck, section of the nose forward of the canopy needs to be stretched by 1/Cos(25) to account for the nose folding in. A paper trace will need to be taken to get the geometry of the nosecone itself right. Chances are i'll get to this one in a week or so.
 

Attachments

  • C-3 Transporter.dwg
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EndeavorRC

Member
That sounds awesome. If you'd like, I can share how I hid the nosewheel retracts and got the battery bay correct. It ties in to the first three formers on the fuse. I intended for it to sit a bit higher for good ground clearance not only with the props, but as for any attachment I may add.

The wing and how it's mounted was something I debated for a bit. I decided to go with 4 wingbolts that go in to blind nuts with dual front locators. There's a large 5ply plate that the wing screws to, that plate is tied into multiple formers and doublers. At first first I was skeptical, but after 30+ take off and landing cycles, it was holding true.

Again, if you're up for discussing it in a more personal form, I'm more than happy to help!
 

b-29er

Well-known member
Welp, not the plans everyone's looking for i'm sure, but if you happen to have a large CNC machine or a LOT of determination, here are the 14' plans. All squares indicate a 1/4" depth cut for joints on 1/2" pink foam
 

Attachments

  • C-3L Super Transporter.dxf
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EndeavorRC

Member
I'll browse the DWG when I get home, I saw the photo and it looked like it's gonna be a monster! I don't know if I've brought this up or not, but the Center Wing Section needs to be absolutely robust. I've been analyzing onboard video of mine (wingtip to wingtip view and center wing camera) since I wasn't sure if I was going to have the strength to absorb the shock of landing and other things. So far, I'm only getting roughly 1"-1.5" of flex upwards across the entire span. The beauty of the brown foamboard is that stress witness marks can be easily seen.

My second version I did made it roughly 68 flights before I started having signs of major fatigue, Granted that was strictly a "design stress test" model. I'm up to 30+ flights with everything logged on this current version with no visible signs of fatigue.

keep me posted on everything ya got going on, it's pretty awesome to see that someone took interest in my build!
 

b-29er

Well-known member
I'll browse the DWG when I get home, I saw the photo and it looked like it's gonna be a monster! I don't know if I've brought this up or not, but the Center Wing Section needs to be absolutely robust. I've been analyzing onboard video of mine (wingtip to wingtip view and center wing camera) since I wasn't sure if I was going to have the strength to absorb the shock of landing and other things. So far, I'm only getting roughly 1"-1.5" of flex upwards across the entire span. The beauty of the brown foamboard is that stress witness marks can be easily seen.

My second version I did made it roughly 68 flights before I started having signs of major fatigue, Granted that was strictly a "design stress test" model. I'm up to 30+ flights with everything logged on this current version with no visible signs of fatigue.

keep me posted on everything ya got going on, it's pretty awesome to see that someone took interest in my build!

I took a couple of artistic liberties with the design, the wings are built like tanks. Clark Y airfoil, 1/2" pink foam foldover for the leading edge and foamboard for the trailing edge. 1/2" ply for the ribs and the main spar, which runs all the way to the tip, followed by two additional spars made of 3/4" aluminum square tube that go 3 and 4 feet into the wing. There's also an aluminum tube that will connect the engine to the two alu spars via 1/4" bolts and an adapter, and to the landing gear, which will also be a 3/4 alu square either directly holding or housing a trailing link system to a pair of 4" wheels. So I don't foresee any stress issues in the wings, engine pods, etc . Fuse, we'll need to see on that.

Most of this is set up so it's easy to build on the grounds at FF. I'll be doing any of the things that gave me a panic attack in 2018 with the b-36 onsite build from home so I can minimize tooling, but dont expect much in the way of flight testing until like...the 15th late, maybe the 16th.

Will keep you posted. Thanks for the flight testing data!
 

EndeavorRC

Member
Awesome! ha, with the plane basically being a box, there's a LOT of room for creative freedom. Naturally, I wanted mine to be larger from the start due to the flying qualities of larger models. I only have one design limitation.. that being the aircraft fuselage and wings (separate) have to fit from the console to the hatch of my SUV with minimal assembly. haha, as long as I keep that number in mind, I'm able to hit the nail on the head in every other area.