Foam Board Baby Hornet

[Flyingshark]

Yesterday I started working on a new plane! I've had a half-finished balsa kit of the Baby Hornet lying around for years, and for complicated reasons [bad workmanship] it will probably never fly. Besides, it's a free flight model.

Here's the link to the original kit: (I got it before it was laser cut)
https://easybuiltmodels.com/ff31.htm#gsc.tab=0

I really like the design of the Baby Hornet, though, so I thought I'd try to make a version out of foam board to run on Power Pack A. The free flight model has a 30" wingspan, so I'll stick with that for now.

Anyway, with that out of the way, here's my progress so far:
I traced the plans for the rubber-powered Baby Hornet onto graph paper, and made a few modifications. (Control surfaces are pretty important...)
After that was done, I just treated them like FT plans (tape, poster board, cut out = template!)

So, that's where I am right now. Later today I'll probably start building stuff.

Also, a question about control surfaces size:
I though the rudder size was a little small, (this will be a 3ch plane, so rudder will be the only way to turn it) so I drew two other profiles. How much larger should the rudder be, if at all?

TL;DR: I'm building an airplane! Please post suggestions!

 

[Monte.C]

Yesterday I started working on a new plane! I've had a half-finished balsa kit of the Baby Hornet lying around for years, and for complicated reasons [bad workmanship] it will probably never fly. Besides, it's a free flight model.

Here's the link to the original kit: (I got it before it was laser cut)
https://easybuiltmodels.com/ff31.htm#gsc.tab=0

I really like the design of the Baby Hornet, though, so I thought I'd try to make a version out of foam board to run on Power Pack A. The free flight model has a 30" wingspan, so I'll stick with that for now.

Anyway, with that out of the way, here's my progress so far:
I traced the plans for the rubber-powered Baby Hornet onto graph paper, and made a few modifications. (Control surfaces are pretty important...)
After that was done, I just treated them like FT plans (tape, poster board, cut out = template!)
View attachment 177655
View attachment 177656
View attachment 177657
View attachment 177659

So, that's where I am right now. Later today I'll probably start building stuff.

Also, a question about control surfaces size:
I though the rudder size was a little small, (this will be a 3ch plane, so rudder will be the only way to turn it) so I drew two other profiles. How much larger should the rudder be, if at all?
View attachment 177660

TL;DR: I'm building an airplane! Please post suggestions!

Go Go Graph Paper!! That's how I started drawing stuff, a long long time ago.
Looking good!

 

[Timmy]

How do you get things to be so symmetrical? You can really draw!

 

[Flyingshark]

Go Go Graph Paper!! That's how I started drawing stuff, a long long time ago.
Looking good!

Thanks! Graph paper is awesome!

How do you get things to be so symmetrical? You can really draw!

I just practice a lot. I find it easier to design a plane up to the experimenting stage on paper, so I have a huge pile of quarter-scale 3 views and specs for planes I might build when my flying skills are good enough that I can tell whether crashes are my fault or the planes fault.

The graph paper helps SO MUCH with keeping measurements roughly right, and using 11x17 instead of 8.5x11 means you can fit a 3 view of a pretty large plane onto one sheet at 1/4" scale. I also use a mechanical pencil, so the tip is always pretty sharp.

 

[Monte.C]

Thanks! Graph paper is awesome!


I just practice a lot. I find it easier to design a plane up to the experimenting stage on paper, so I have a huge pile of quarter-scale 3 views and specs for planes I might build when my flying skills are good enough that I can tell whether crashes are my fault or the planes fault.

The graph paper helps SO MUCH with keeping measurements roughly right, and using 11x17 instead of 8.5x11 means you can fit a 3 view of a pretty large plane onto one sheet at 1/4" scale. I also use a mechanical pencil, so the tip is always pretty sharp.

You know the desk pad that some people have on their desk in their office? So they have a nice surface to write on instead of writing on the hard desk. When I was a young guy I had a desk pad that was a pad of 1/4" graph paper. If you're loving what you're doing you might get one.

 

[Flyingshark]

Started cutting and glueing foam board!

The 850mah 3s fits perfectly in the bottom of the fuselage! Now I have to figure out where everything else goes.

I decided to go with the largest rudder profile to try and make sure I have more than enough authority. I'm trying to build the wing as simply as possible because the chord is only 4 1/4 inches. And I'm crazy enough to want to do a fold-over airfoil. I wonder how successful that will be. [Hint: probably not very]

 

[Timmy]

Started cutting and glueing foam board!
View attachment 177677
View attachment 177679

The 850mah 3s fits perfectly in the bottom of the fuselage! Now I have to figure out where everything else goes.
View attachment 177678
View attachment 177680

I decided to go with the largest rudder profile to try and make sure I have more than enough authority. I'm trying to build the wing as simply as possible because the chord is only 4 1/4 inches. And I'm crazy enough to want to do a fold-over airfoil. I wonder how successful that will be. [Hint: probably not very]

looking awesome!

 

[Grifflyer]

Great work so far!

 

[Flyingshark]

Great work so far!

Thanks!

 

[GrizWiz]

Started cutting and glueing foam board!
View attachment 177677
View attachment 177679

The 850mah 3s fits perfectly in the bottom of the fuselage! Now I have to figure out where everything else goes.
View attachment 177678
View attachment 177680

I decided to go with the largest rudder profile to try and make sure I have more than enough authority. I'm trying to build the wing as simply as possible because the chord is only 4 1/4 inches. And I'm crazy enough to want to do a fold-over airfoil. I wonder how successful that will be. [Hint: probably not very]

You should get new knife blades your blades are getting caught on the inner foam!

 

[Flyingshark]

You should get new knife blades your blades are getting caught on the inner foam!

Yeah. I bought a 100 pack a while ago, but I think I'm going through them a lot faster now!

 

[GrizWiz]

Cool!

 

[FoamyDM]

Keep at it. It's looking good!

 

[Flyingshark]

Almost finished!
The fuselage is basically done now, just needs some skewers for the landing gear and the removable wing.

I used a slightly wider than normal mighty mini power pod. The back part of the pod had to be cut down so the motor would fit at the front end of the nose curve.

In the morning tomorrow, I'll tackle the wing, before I go flying with my friend in the afternoon. Ambitious timing, I know. Still, how hard can it be?

 

[Flyingshark]

Q: How hard can it be [to build a foam board wing] A: Pretty hard.

Wings with dihedral are kinda difficult (at least for me), and this one was thin enough I couldn't do a normal spar joint like on the FT Spitfire. I used barbecue skewers instead. Also, since I'm not a CAD genius, I had to eyeball the wingtip shape, and cut that AFTER I had folded the wing.

Aaand, here's the (nearly) finished product! It just needs some landing gear and to velcro the electronics in place.

I really need to clean my workbench.

 

[Flyingshark]

I finished up the Baby Hornet today! My backyard is barely large enough to get it going in a straight line, but I did make sure that it flies.

I built removable landing gear, and promptly decided I hated it, so I didn't use it. The battery had to go right up under the power pod to get it to balance right. It might need a little foam board skid to protect it more.

 

[Flyingshark]

Flight video! This is just a compilation of about half of the flights I did today. Hopefully I can make the trek to a larger area soon and fly for longer.

 

[The Hangar]

Flight video! This is just a compilation of about half of the flights I did today. Hopefully I can make the trek to a larger area soon and fly for longer.

Looks like it flew pretty well! Congrats.

 

[Flyingshark]

Flew the Baby Hornet again today, at a larger field. I'll upload the video tomorrow.

The wind was very strong, so it made the plane do lots of things I didn't mean it to do. Like flying over a ridge and landing in a small boat parked on the beach. All while I'm giving it full throttle against the wind and full down elevator. (Imho, crashing on land is a lot better than on the water) The worst damage was a broken prop from landing out of an unintentional loop.

And even though the power pod wiggles after all the smacks into the fence yesterday, the rudder isn't on right, the wingtips are smooshed and the receiver falls out of the back of the plane every time I throw it, IT STILL FLIES!!!

On a more serious note, after I get this one dialed in, I might build another with alignment tabs for the rudder and hstab, some battery protection, and ailerons or flaperons.

 

[Flyingshark]

Video!