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Hi everybody, I am actually snatch my hairs with a 6-seats capable shuttle design I am working on. It is clearly inspirated from the now well knew Dream Chaser, but it gives me so much problems that I surnamed it Doom Chaser. I worked on two different variants : The A is about endurance with about 3 km/s of dV available : And the B much more for aerodynamic performances test craft : In both case they are my first attempts to place a medium orbiter with enough lifting surface at the top of a launcher. All the others concept were placed in a booster/fuel tank-riding position and their lifting surface was just sufficient to ensure them to safely glide back to home. Here the situation is totally new to me, the CoL is far away from the CoM and CoT more important. The result is a lifting force too important to be countered by the vectored thrust, the whole shuttle flipping all the time once the dynamic speed becames sufficient to gives the orbiter wings and body enough lifting force : 42 m/s relative speed is still to low to give the orbiter enough lift. 50 m/s and the problem starts to appear. Logically the autopilot tries to counter it by max gimballing the engines and it gives some results. But as a simple computer it will not keep on gimballing the engines and will wait for new problematics information to come. About two seconds only after the lifting force is so important that event he thrust can't counters it anymore. I've tried a booster riding configuration too to bring the CoL closer to the CoM but the result is absolutely the same. Of course I could also place it in a fairing to erase that problem definitely but it will ask for a larger and costful launcher. Is anyone of you with more knowledges got ideas ? (I should have studied more seriously my manuals about aerodynamics some years ago...)