lantinian,
Very interesting and thoughtful perspective. Thanks for taking the time. My thoughts, FWIW:
As far as vastly exceeding speed and range, that's true. However, clearly Army wanted to look at a variety of technologies, a good plan. if they set those requirements much higher, they would have effectively pre-selected Tilt-Rotor. Again, what Bell is doing is leveraging the power they're going to have to have to meet the 6K 95F requirement anyway and harnessing it fully.
Regarding the V-22's problems, AFAIK they haven't been related to how it tilts its proprotors, or even to the fact that it's a Tilt-Rotor. Regarding Presidential use, I'm not sure how you can state the US President will never get one since there are already 12 being delivered to HMX-1 for support roles and to fly the press and other personnel. As far as Marine 1 goes, the V-22 is considerably larger than the existing assets (note pic), so that's a consideration--do we need one that large? Plus, they love to have their competitions, you know, so they're going to have another one for that. On the other hand, maybe with something this big, they can carry all the stuff the Secret Service keeps wanting to pile in there, which is what killed the VH-71. Depending on what they want the new one to do, the V-22 may indeed get bid. Boeing is also considering separately bidding the CH-47. In any case, President Obama doesn't seem to be too worried, as he tends to use the V-22 abroad when its available, something neither he nor the Secret Service would tend to put up with if the complexity seriously affected its ability to perform its mission.
There's actually a complexity you left out regarding the concept under discussion. Specifically, since its propellors are not in line with the with the engines (as they could be on an engine tilting Tilt-Rotor but not on a fixed nacelle one), you've got to have some kind of power transfer case in there. Granted, it won't have to move, but it's a complicated gearcase nonetheless. Plus, you have the thrust vector not in line with the motion of the a/c, which has to add stress to that gearcase and mount (Tilt-Rotor has it too, but normally only for a small portion of the flight, and only at lower speeds).
Not sure how this concept would be more survivable. A 57mm hot in the nacelle of a Tilt-Rotor or this is pretty much going to take out everything, and with this concept you have the additional vulnerable area where the wing tilting mechanism is. In both cases, BTW, the heavy engines are sitting out on the wing tips. OTOH, both concepts can land safely with the props forward, but this one can do it more nicely.
On a conventional helo, you have a lot of moving parts in the rotor hub, and it gets really complex in there. Possibly even more so for X2, but not to a dangerous or unacceptable level. Of course,with X2, should that rear prop or related shaft be knocked out, it looks like it'll be slower than a conventional (a conventional helo in this situation immediately become a thrill ride).
I don't think I'm using different fruits here. It seems the the rotor-wing interaction is going to be a function how much the blades overlap the wing in Tilt-Rotor or VI wing some will get deflected aft and down because the wing has some tilt on it in the hover, but it still going to have the downforce impinging on it as a function of wing area and overlap. It will be reduced in forward flight because of the effect that forward motion will have on the displaced air, but it'll still be impinging on the wing.
I guess all I'm saying is that it seems that what you have to give up with the VI wing concept seems an awfully high price to reduce what doesn't seem to be to be that much of a problem.
Again, FWIW
