Thanks for the link Jarno (even better would be the aborted first flight attempts showing the ground looping --which disclose the problem with wing clearence and the low inertias -to their credit the Akafliegers posted the problematic flights as well as the end result . They still had problems on aerotow with the downwash of the tug tending to de stabilize the aircraft (reducing the angle of attack of the centre part of the wing and hence 'removing' wash out from the glider --in Australia we 'low tow' and stay under the tug's slipstream unlike the high tow used in Europe and the US so this would be presumably worse . [As an aside - my first flight in Germany was in the werkgruppe std .Cirrus -- never flown a Std Cirrus before and only got a very rudimentary briefing so I just did the usual and stayed in low tow which was apparently an emergency signal and I got towed around at tree top height until I cottoned on and went to high tow -- I came back a couple of hours later and nobody even commented ... I was told that it would be too hard to even get to fly in Germany first off but after presenting myself and logbook to the control tower at Hahnweide they gave me a luftfahrtshein without any hassle at all and a vague indication of where the Stuttgart approach zone was to avoid --I expected a check ride in a two seater or something but got dumped in the std cirrus and told I could fly it "so lange du wilst" . Also had never done any slope soaring before let alone with thirty or more other aircraft on the same ridge (Teck) so learnt fast .] The problem with tailess gliders is not always just how they behave in the air but what happens on take off and even more so on outlanding -- landing in a tall crop for example could be more than just exciting . We just had a motorglider accident here --a picture in the paper shows the aircraft belly up which is uncharacteristic of sailplane accidents but the tractor engine and conventional gear explain why --looks like it might be a Pipistrel Sinus or Dimona (only slight injuries happily) Forward sweep might be a solution provided the aeroelastics can be solved --the mildly forward swept Genesis is as good as the other tailed gliders it seems (and is semi tailed if it is being exact ) -- several highly forward swept gliders have failed --the Akaflieg Darmstadt "QuoVadis" as one example and the difficulties the SB13 had with flutter suppression and handling with aft sweep give cause for even more concern. The tailoring of the SB 13 to avoid flutter and placement of the spar far forward at the tips can result in control reversal in the extreme --the 'aeroisoclonic' (constant angle - under bending) such as the Short Sherpa was meant to avoid the instability that can result if the wing is too compliant (the spar is further AFT at the tips to counter the twist due to bending ) All in all the structural interactions in a pure flying wing and the ground handling habits are a big concern and reason enough to stick with conventionality - or try something else..