Scale Glasfugel Libelle 201 - in Depron!

[quorneng]

I restored a moulded foam Easy Fly ST330. Of course it is not scale but it could have been moulded in any shape, although it might not fly so well.
I was always impressed by the Libelle. One of the first production glass fibre gliders at the time it had an exceptional performance for a standard class 15m glider.

It was technically clever too being very light and incredibly easy to put together with all the controls but the ailerons being self connecting. The tailplane was secured by a single tiny bolt and the wings by a single pin.
The problem with scale model based on a high performance glider is that the wing chord tends to be very small. Wing chords less than about 75mm (3") tend to to be rather inefficient.
My intent was to build a scale glider using the lightweight balsa/Depron mix I had used successfully on several 'own design' electric gliders.
To save weight these all had one piece wings but to achieve a reasonable chord the Libelle would have to rather bigger 2.8m or more.

To get an idea of the construction I built a short root section test section of a one piece 2.8m wing.

All 3mm Depron it has a step in the skin top and bottom to accommodate
the wide 1mm balsa spar flanges. Only a part of the flange has been added.

The wing across the fuselage is flat with dihedral at each wing root.

The Wortman section is really quite thick (18%) for a model glider.

But it is nevertheless very strong and stiff yet incredibly light.
This rather tipped my decision in favour of a one piece wing but limited to 2m and suffer the penalty of very narrow wing chord.
The wing and fuselage profiles 'tile' printed to 2160mm span and 896mm fuselage length.

Now I have just got to work out how to make it!