Amazingly enough, if you go to the web-site for the American Helicopter Society, you'll find 50 odd academic papers on Osprey aerodynamics - but there were obviously no studies done on the V-22's susceptibility to "vortex ring" (let alone asymmetric vortex ring). If you go to NASA AMES and NASA Langley sites and search similarly, you'll find zip. There are plenty of learned treatises on literally
every other aspect of the Osprey's aerodynamics - but the one "biggy" slipped through the cracks.
They did run a quarter-scale model through the AMES wind-tunnel at NAS Moffett.
http://quest.arc.nasa.gov/aero/team/...g/ly12-29.html
But it appears that vortex ring wasn't on the test schedule.
[This message has been edited by UNCTUOUS (edited 14 May 2000).]