Sig Banshee Controline

[Ricardo]

Guys, some pictures of my latest controline model, a Sig Banshee.

It is designed for 0.35-0.46 cu.in. motors. I am using an OS 40FP.

I built it from a Sig Kit:
https://sigmfg.com/products/sigcl11-sig-banshee-kit

I usually dont post while I am in the process of building. I prefer to post it all after its done. So here it goes...

[Ricardo]

The plane was designed for a time when noise was not an issue. So most of the modelers did not use mufflers, therefore the engines ended up lighter.

Nowadays there is a bigger concern, so we consider the use of mufflers from the start.

To account for the added muffler weight, it is advised by the kit manufacturer that the nose of the airplane is shortened by 1-1.5 inches.

See pictures of shortened nose:

[Ricardo]

I proof installed the engine and tank.
One thing I did for the first time - I used a CNC Router (another hobby) to drill all holes and cut the fuselage nose into shape.

It was exciting to see the motor, tank, landing gear, all fit perfectly in position. All holes true and aligned!

[Ricardo]

Bellcrank mount: this is where the lines movement get translated into a linear push-pull motion, to move the flaps and elevators.

It is critical to build it strong and friction-free. All the control in a controline model depends on the tension in the lines. And when the lines get less tensioned, any friction is the enemy of the model controlability.

This bellcrank includes a bearing, to minimize friction.

This assembly needs to support 10x the mass of the airplane. This airplane should be in the 1300g ballpark AUW, So the bellcrank/ cables need to support roughly 13 kg (29lbs) in this kind of model.

[Ricardo]

Putting all pieces together to have a feel for the overall fit, and ballpark CG location.

I did some changes to the Kit, including:
- Flap chord and span - increased chord and reduced span - testing to compare with my other models;
- Wing leading edge - added sheeting - For added robustness and better aero;
- VStab increase - for looks only;
- Hstab increase - for looks and to match other more modern airplanes;

[Ricardo]

An idea of the size of the model.

It is considered a medium - large controline model.

Note that in the outside wing I added a trim tab. The idea is to adjust in case the airplane is not flying laterally leveled.

[Ricardo]

Painting - Personal preference to paint before covering.

[Ricardo]

Wings Covered. Note the trim tab on the outside wing, not covered yet.

[Ricardo]

For this airplane, I wanted a Canadian theme finish.
Therefore, red and white were mandatory.
At the same time, some metallic colour would add to the mix.

I picked the metallic red for the fuselage. And chose golden for the wing decoration

After many sketches, the winning scheme is seen in the picture below...

[Ricardo]

Details of the motor and tank can be seen below:

[Ricardo]

Aircraft is almost ready for flight - I did an engine test run and the fuel tank was leaking - So I had to replace / repair.

Hopefully flies soon! Looking forward to it, and quite nervous - After so much work...

Will let you know how it goes.

[Jdonald]

Nice build and great looking plane.

Years ago with the Cox .049 if I remember correctly I used 20 foot long control
lines.
With your size engine how long will the control lines need to be?

[Ricardo]

I am using 18-metre lines, which is around 60ft.

[Sempai-mj]

Cool build, nice Spinner and prop.

[Michael O'Bree]

Thanks for sharing, Ricardo. Great to see a Controline Master at work - congratulations.

[Ricardo]

Thanks Michael! Far from being a master!

[Xavier]

What ratio of elevator - flap angle do you have on this one and the electric one ?

[Ricardo]

Hi Xavier, I usually use 1/2 to 2/3 of the elevator deflection.

I find it does not make too much difference on very wide maneuvers such as loops. It will make a difference on tight corners though, such as triangles and squares.

But i have not read much about it.

This site usually has very good technical content:
http://flyinglines.org/index.html

Cheers!

[Ricardo]

What ratio of elevator - flap angle do you have on this one and the electric one ?

Check out this thread:
https://stunthanger.com/smf/building-techniques/elevator-to-flap-ratio/

[Xavier]

Thanks for the links and info Ricardo. A lot of reading :-)
Xavier