Having once seen this one personally, under testing and operating in proto type stages at NASA, Moffet Field, Ca (KNUQ).. I would guess it were older ... (defense.aol.com) More...
I used to live only a few miles from Quantico, and V-22s, CH-53s, and CH-46s would fly over my apartment on a regular basis. They all have their own unique sound and feel. It's hard for me to believe they've been operational for 5 years already.
And yes, the V-22 program is a LOT older than 5 years - the first test flight was in 1989. All the problems they had with the plane (especially conversion from vertical to horizontal flight) led to the near-cancellation of the program. Modern computers are what allow the conversion to work properly.
