Chinooks. Not exactly stealthy, are they?
Caveat: I know naaaathiing, this is a genuine question.
I was working in my garden office this afternoon when I heard *that* sound (not unusual in my area). I was due a break, so I wandered out and looked west. A *long* time later a Wokka hove into view at reasonably low level. It occurred to me that in a hostile environment I'd had enough notice to order a MANPAD on eBay with a pretty good chance of it showing up in time. Is it just me, or does these things announcing their arrival quite so well make them a little... vulnerable?