Well just an update, the Shark 304 is 95% finished, the Up and go works perfectly, I just weighed it 17.o kg (about 39.5lb for our american friends), and cg probably slightly forward, but it is easy to remove weight, the Elicker unit works perfectly, all there is to do is to set up the control surfaces, which is simple with Weatronics, and the wait for fine weather, which is not so simple, we are having a very mild winter, temps about 60F-65F during the day, but showers most days. Hopefully in September we will start to dry out and I can maiden this plane.
I checked the cg, using a balance unit I use for my jets, (unfortunately it is not very sensitive) and also by using 2 scales, one under the main wheel and one under the tail wheel and the calculating the moments, the same way full size sailplanes are checked. The 2 methods gave very roughly similar results, close enough for a maiden flight.
One item, down here for model planes we have a ruling from CAA, that any plane over 15kg has to have 5 test flights before it can be flown at a public display, and of course anything over 25kg has to have a special dispensation to fly.
Basically the 5 flights for sailplanes such as the 304 are a safety measure, as it would be unusual to fly when the public are around.
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