Mad Hatter F3-RES

F3-RES is a new low technology class thermal soaring class. It's well established and popular - in German and USA making good use of modern wing sections, limited Carbon or Glass Fibre components. Models tend to very light and have excellent performance if built accurately.

A small group of us in BARCS are trying to get the class introduced into the UK, initially as a class for a postal event - and if this grows then we hope to encourage local, regional and national events.

Flights are flown in 9 minute 'slots' with a 6 minute maximum and spot landing bonus. Launch is via a standard bungee and towline which should get the model to about 80-90 metres before release. Models must be built from wood (predominantly) with composite materials allowed for the boom, tail and wing mounts, wing spars and wing joiner. EPP, other foam or moulded flying surfaces are excluded.

I am planning to build an own design glider, named 'Mad Hatter'.

 It's basically a condensed version of my Cheshire Cat 100S design - which at the time of writing is still being built. There is misplaced coincidence for you.



The wing section is the well proven Mark Drela AG35. This uses 10x0.5mm Carbon Fibre caps over 10mm wide balsa 'webs' (in reality the spar) and 6x0.6mm caps in the tip panels. No Kevlar thread spar winding will be needed in this model, it does not have to carry the load of a winch launch.

This is sheeted as far as the 'flat' sections of the airfoil with covering support spars at the rear

I am getting quite interested in carrying out stability predictions and using my spreadsheet I have the following:

The model will undoubtedly change as my thoughts develop over the next few weeks but this is my starter for 10.

Lavoie method of building Stick Model Aircraft Fuselages

Posting this for posterity so that I don't lose these links again. I use a derivative of this method and as time moves on I use more of the ideas presented.

Three videos - well worthwhile watching if you are building lightweight rubber power scale models for indoor or outdoor use.

Part 1

Part 2

Part 3

Highly recommended