Coming a bit late to this fascinating thread.
I think that the emergency landing scenario is not too much of a problem. When a conventional helicopter suffers a loss of power, it can usually carry out a controlled decsent under autorotation. The proviso with the present craft is that it must first transition to vertical flight. But when near the ground it will already be vertical, it only transitions to horizontal flight at an altitude where the reverse transition to an autorotative descent can be made.
My main concerns lie with the overall weight and efficiency of the design. Several things seem to militate against it.
The first is that for part of the transition cycle only two wings are providing any significant lift. That works out at 25% of the maximum available loading at takeoff - or, the craft carries 4 times the wing area needed to support it at 100% loading. Most conventional aeroplanes carry less than 1.5 times the wing area needed at 100% loading. So the claim that the total wing area can be reduced here seems questionable.
Another issue is the need to compromise the rotor twist and profile between cruising and vertical modes. The V-22 Osprey tiltrotor has this problem in spades, and it has limited the maximum cruise speed to little more than an advanced helicopter. The proprotors have much higher drag than predicted when used as propellers, and much effort to fix things has had little effect. With more rotor effort put into overcoming that drag, on the present design less is then available for lift during cruise, reducing net aerodynamic efficiency. The patent looks like there is a blown slot system to try and get round some of this. Such systems usually need a lot of air, with the accompanying extra power, and the ducting makes those wings heavier and harder to keep rigid.
There is a way to generate lift from more surfaces by varying the angle of attack appropriately, but that comes at the expense of reduced forward thrust, so the reduction in wing area this makes possible is unlikely to result in improved forward speed. The truth is, you need far more area for lift than you do for efficient thrust and all that extra area just causes extra drag. A "flapping" or individual cyclic variation in speed of rotation is also possible, but I know of no successful active power-driven flapping application.
High torque forces must be transmitted between the two rotors. If the rotors are mechanically coupled to ensure contra-rotation, that long coupling/drive shaft has to carry the main torque. I doubt the rotors can safely be electronically coupled with separate power sources, as the single-engine-out situation would create severe torque problems. During violent manoeuvres, such as hitting an air pocket while undergoing a flight transition, these forces will act in weird directions, and all that must be passed by the main bearings into the fuselage. Then. there is the fuselage torque control system. Hooking that into the wing dynamics adds another layer of complexity and failure modes on an already challenging system. I really think it needs to be separate. That will add weight, hence drag, with no compensating gain in lift.
Finally, I assume that the weird forces acting on the wings - a mixture of aerodynamic and inertial - during all flight modes have been factored in: these wings will need to combine great stiffness with low mass, and conventional rotary wings are already a challenging enough problem. I don't envy the designer who has to run large ducts through them too.
If all that can be overcome, then it would be great to see a viable prototype in the air.
