21st Century, in your misguided zeal to defend the V-22 at all costs, you try to divert the discussion. If you honestly want to stay on point and add to this discussion, then why not address what we're talking about here, which is what I see as the biggest flaw of the V-22: a low-level encounter with A-VRS is simply not recoverable and therefore unsurvivable. I know, I know...all you have to do when you sense that you're experiencing A-VRS is beep those nacelles forward and fly away! I say: by the time you realize you're getting into A-VRS it will likely be too late because you've already aggravated it by making an opposite control input (as happened to Majors Brow and Gruber).
The rates of descent experienced by Brow and Gruber were not sustained; they were merely transitory as they tried to maintain position on their Lead aircraft, the other V-22 (which also crashed, only level). Anyone who thinks that they intentionally initiated a sustained RoD of 2000+ fpm at 800' is insane. But that has become the narrative of the blame-the-pilots-not-the-aircraft group. The problem with Brow and Gruber's V-22 was that once they started coming down, that one proprotor got into VRS and over she went. Would not have happened that way to a CH-53. Would. Not. Have. Happened.
No, I don't know how hard a CH-53 can hit vertically and still be survivable. But I do know that it's better for ANY aircraft to hit upright to allow the landing gear and structure to do the job it was designed for than to crash inverted. Or do you dispute *that*?
Yes, yes, we know that VRS of any sort is difficult to get into when you're trying to demonstrate it. Fact is, the conditions that make it happen are not easily or dependably reproducable - unlike, say, the stalling speed of an airplane wing. Trouble is, when plain-vanilla VRS does happen it usually catches pilots by surprise, like when they're busy doing other things. Even a fairly "easy" shallow-but-fast straight-in landing can put pilots in a "task overload" situation as we saw in the Afghanistan V-22 crash. What makes us think that a steep, circling, improvised, possibly downwind approach (due to conditions being different than planned) won't result in the same thing...only worse? And A-VRS is *much* worse!
Arguing over comparisons between helicopters and tilt-rotors as to relative rates of descent needed to excite VRS is useless and irrelevant. I've said it before and I'll say it again: Only V-22's can get A-VRS. And low-level A-VRS is unrecoverable and absolutely unsurvivable. Saying...praying...pleading...promising it won't ever happen again is just silly. It will. The fact that it has so far not happened yet is no guarantee that it won't, and you know it.
End of story.