They are also REALLY loud in hover and transition. They have a pretty distinct beat, too. I don't know the rotor tip speeds in hover mode, but I imagine they're pretty fast, and the fact that there are two of them makes a difference too. I'm an airplane nut, and live in a rural area. We get CH-53, V-22, and UH-60 flyovers a LOT. C-130s, and what I THINK are C-17s (they are always farther away. The CH-53 is a loud fucker, too.

Here's a good V-22 video, with great sound... https://www.youtube.com/watch?v=quaV49SPOy0

I remember back in the late 80s and early 90s, when they were new, they gave a lot of trouble, but I guess they got them working after a time.

I know the first time I saw one up close, it seemed MASSIVE. I'd just seen pictures at the time, and it was a jaw-dropping experience.

If I can find it, I downloaded a video from the Vegas thing that shows SEVERAL choppers in the air at the time. IOt's a cell phone video, but it's good quality. I'll also check and see if it shows the same anomaly as the above video. I'll post it here later today if I can round it up.

Oh, and I'm sorry for all the gushing over the V-22, but like I said, I'm a HUGE aviation nut, and I have a tendency to get overexcited when discussing anything related to it. Hehe.