Interesting AVR pics.
Trying to understand this - does this comes about from a combination of the slow speed & sink rate that effectively puts the rotor in its own vortex and messes with its usual lift? This also effectively limits ability to control lift for long enough for a big diffential to be created from one side to the other - creating a moment / roll that can't be recovered from?
I guess the only answer here is to avoid such a sink rate/forward speed? Is this programmed into the Flight Control System logic (as with carefree handling in other aircraft?) - or are the pilots just trained never to go there? Can you imagine Boscombe trying to certifying this aircraft!
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Having seen one operate at Farnborough last year - I think it is pretty clear this type of capability is the future (unless affordability issues with the technology render it a bit of a concorde - this shouldn't be the case though). If you look at how often Harriers / Kestrels did unconventional landings (i.e crashed) in the early days, Ospreys development history is not unexpected.