FTFC20 Opel Rak 1 designed by Dr. Looping Looie

[Bo123]

Ok thanks.

I

It's a fun build and some how these old plane's look totally awesome.👍

 

[Matthewdupreez]

@Dr. Looping Looie where is the CG of this plane??

 

[Dr. Looping Looie]

@Dr. Looping Looie where is the CG of this plane??

1/3rd of wing chord. theres a very wide range of flyable cg

 

[Matthewdupreez]

1/3rd of wing chord. theres a very wide range of flyable cg

Ok cool thanks...

 

[Baron VonHelton]

I

It's a fun build and some how these old plane's look totally awesome.👍

HARK!

 

[Matthewdupreez]

Finished besides electronics...
Did some slight modifications to get it to use a 6" prop...
Should fly better with the extra thrust.

 

[Matthewdupreez]

1/3rd of wing chord. theres a very wide range of flyable cg

From my glide tests ..
My nice slightly nose down glide..
It's CG is approx 1/2 of wing chord...
1/3 gives me a very nose heavy glide...

 

[Monte.C]

So, wings and tail are done!
New technique!

I will add reference lines in the plans so that everything will be nice and straight!

First, its important that you really bend a nice curve in the foam. That will make it much easier for the ribs to hold the shape. Then apply glue to the top side of the ribs and glue them in one at a time. Allways check your angles and try to get them as equal as possible! Use the leading edge to line them up.
View attachment 140943
Thats how it should look with the ribs installed:
View attachment 140944

Then apply glue to the bottom of the ribs and glue the bottom plate on:
View attachment 140945

And the wing is done! Allways double-check so that you dont get accidently wing warp.
View attachment 140946

Next is the tail section and the fuselage!

The way you're building these wings has really got my imagination going. My mind keeps revisiting the concept every now & then. I've already been building with formers; I think one of these days I might be using the idea of your bottom plate just like that.

 

[Matthewdupreez]

The way you're building these wings has really got my imagination going. My mind keeps revisiting the concept every now & then. I've already been building with formers; I think one of these days I might be using the idea of your bottom plate just like that.

It goes together very well

 

[Scaddict61]

Do you think it would work with an edf motor installed behind the pilot under the wing widening the fuselage structure?

 

[Dr. Looping Looie]

Do you think it would work with an edf motor installed behind the pilot under the wing widening the fuselage structure?

Yes, but make sure that the EDF can get enough air. You should not get bigger than a 50mm unit, but I think 40mm might be too small. Use the Pilot hole as an air intake, and maybe two NACA ducts on the sides.

 

[Scaddict61]

Yes, but make sure that the EDF can get enough air. You should not get bigger than a 50mm unit, but I think 40mm might be too small. Use the Pilot hole as an air intake, and maybe two NACA ducts on the sides.

Thank you fir your answer, but reading better you message i am not sure i understood well. i actually meant something like what i have tried to show in the attached picture ( hopefully it is understandable ) . I plan to build a reduced and lighter version, something like 85 cm span, using ultralight carbon fiber tubes instead of the spruce

btw Merry Christmas to all of you!