Boeing Rotorcraft Systems (formerly Boeing Helicopters and before that Boeing Vertol) is the former name of a US aircraft manufacturer, now known as the Mobility Division of Boeing Military Aircraft, a division of Boeing Defense, Space & Security. The headquarters and main rotorcraft factory is in Ridley Park, Pennsylvania, a suburb of Philadelphia. Production of Apache attack helicopters in Mesa, Arizona, formerly part of Rotorcraft Systems, is now under the Global Strike Division of Boeing Military Aircraft.