Scratch built DTFB "CUB" Style plane

[ViperTech]

So here is my first attempt at designing and building a CUB style trainer. I used no plans just started drawing on the dtfb and this is what came out. It has a 34" wing span with a 6" chord Armin style and a 27"carbon arrow for a spar, the fuselage is 24" long 2" wide. The landing gear is 3/32" wire on the main part with .055" wire support soldered and mounted in hobby plywood. The firewall is plywood and is the same size as the swappable firewall, the fuse is constructed from formers being applied to the flat fuse sides. The ESC is in the upper part of the nose and covered with a removable cowling and the battery is in the lower section that is large enough for up to a 1550 Mah 3s battery. The motor is a rctimer 2212/10 lots of power. It flies very well and a friend of mine has (hope fully) the maiden flight on video! I messed up on the maiden and did not set up the rates and it was wicked responsive, thankfully I got it down in one piece! Just got back from a flight session tonight and it is just wonderful!

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Active hood scoop made out of plastic spoon
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Cooling vent for ESC
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It is kind of a rough draft so I have no tape on it, just used a marker to color it. No shocking designs just a first attempt at building without using a premade plan. What do you think?

 

[earthsciteach]

It looks great! I really like the landing gear. Very nicely done.

 

[Ron B]

Gerold
good job and the landing gear does look good. I like your cowling and mounting system.
kf wing?

 

[ViperTech]

Thanks earthsciteach!
Thanks Ron B!
The wing started out as a KFM2 but I have folded 2 too many wings so I added the carbon arrow as a spar and it wound up more like the Armin style Ed from Experimental Airlines makes. I would say it might be sort of a hybrid of the two designs. Here is a profile view of the wing, I capped the ends with poster board. I used a household iron to contour the top trailing edge so its not an abrupt squared off edge, that may not be the best idea as it makes the air flow smoother off the top of the wing and that might make it faster? I don't really know!

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[Coleman]

Your cub looks wonderful, can't wait to see the final version. Hopefully we'll get to see that video soon? I never really understood everyone's obsession with the "Cub" airframe until recently, I don't know whats changed but I've really been feelin it lately. Great work.

 

[Bishop]

Nice work, love the spoon scoop

 

[ViperTech]

Thank's Coleman, I guess the Cub is just classic shape when you think of an airplane, for me I just wanted a sturdy top wing plane as I prefer slower flight, how ever to my suprise this plane is not so slow! Kinda keeps me on edge when flying and esp. landing!

Thanks Bishop! I can't take credit for the spoon idea, I saw it on a post some where and I had to use it, just looks cool! At least to a car guy like me! I really like your first plane and it was cool to see it get up! Keep plugging at it!

 

[ViperTech]

MAIDEN VIDEO FINALLY

I got the video from my friend who recorded the maiden!

 

[RAM]

Nice video!

Were you able to dial it in during flight? I think I would have crashed pretty quickly with it being that twitchy. You did a good job getting it to a crash safe altitude.

 

[ViperTech]

Nice video!

Were you able to dial it in during flight? I think I would have crashed pretty quickly with it being that twitchy. You did a good job getting it to a crash safe altitude.

Ram, I have since turned the rates way down and jacked up the expo. I fly it at 45/30 on the ailerons and the elevator at 60/20 my ORX t-six radio.

It is a quick little plane, I am seriously surprised at how maneuverable the thing is for a top wing plane, I was kind of going for a trainer but wound up with more of a sportster by mistake!

 

[RAM]

Thanks for the rate and expo info. I still haven't flown my first bird and those numbers sound like a good starting point. I'm making a not so pretty copy of sr71afans Big Floppy Wing. I wanted something extremely slow flying to start out.

p.s. That's a nice mistake you built