United Technologies may be a Fortune 500 company, but it’s not a household name – and most people don’t realize that the maker of Otis elevators and Carrier air conditioners and heaters is a major military contractor. The Hartford, Connecticut-based company makes military helicopters, engines and missile systems. Its subsidiary Hamilton Sundstrand creates flight systems for both commercial and military aircrafts, while UT subsidiary Pratt & Whitney designs and manufactures engines, gas turbines and space propulsion system for military aircrafts. In 2003, United Technologies also acquired the British electronic security company Chubb Ltd.