The U.S. Air Force has awarded a $9.36 million contract to a Phoenix-based computer services company which will use the money to purchase as many as 18,000 iPad 2 units. Bloomberg reports that the Air Force is purchasing 32GB Wi-Fi models, which will be used as replacements for paper manuals and navigation charts used by pilots and navigators. “Aircrews fly nonstop worldwide missions and require access to flight publications both on and off the…