Helicopter enthusiasts: check out my webpage on my book for Random House, The God Machine: From Boomerangs to Black Hawks, the Story of the Helicopter. It's a social history of helicopters, inventors, and pilots. It came out in 2007 and the paperback followed in 2008. Had a great editor on that project, John Flicker of Bantam Dell.
I got interested in the subject of what helicopters could, and couldn't, do while researching a chapter to add to Inviting Disaster on the World Trade Center evacuation. Scientific American named it as a holiday book pick for 2007.