A Pleasant Surprise

As I was waiting for the Blough, I heard a rather distinctive sound.  Of course I turned in the direction it was coming from.

 Much to my surprise it was a CH-47 Chinook Helicopter.  I don't normally see those in this neck of the woods, so I was pretty happy.

 The Chinook Helicopter came about because the Army needed a heavy lift helicopter.  In 1958, after a competition, the Army awarded the contract for this helicopter to Boeing Vertol.  It's first flight was in 1961 and it was introduced to the service in 1962 (compare that to how long it took to introduce the F-22 sometime).

 Over the years, it has seen a number of upgrades and have been used by a number of US Allies.

The current model is the F model, but I'm not sure what this one is.  It is a pretty cool looking helicopter though.