The Northrop Grumman (formerly Ryan Aeronautical) RQ-4 Global Hawk (known as Tier II+ during development) is an unmanned aerial vehicle (UAV) used by the United States Air Force and Navy and the German Air Force as a surveillance aircraft. The Northrop Grumman B-2 Spirit (also known as the Stealth Bomber) is an American strategic bomber, featuring low observable stealth technology designed for penetrating dense anti-aircraft defenses; it is able to deploy both conventional and nuclear weapons. The bomber has a crew of two and can drop up to eighty 500 lb (230 kg)-class JDAM GPS-guided bombs, or sixteen 2,400 lb (1,100 kg) B83 nuclear bombs. The B-2 is the only aircraft that can carry large air-to-surface standoff weapons in a stealth configuration. The BQM-74 Chukar is a series of aerial target drones produced by Northrop. The Chukar has gone through three major revisions, including the initial MQM-74A Chukar I, the MQM-74C Chukar II, and the BQM-74C Chukar III. They are recoverable, remote controlled, subsonic aerial target, capable of speeds up to Mach 0.86 and altitudes from 30 to 40,000 ft (10 to 12,000 m). Northrop Grumman Corporation (NYSE: NOC) is an American global aerospace and defense technology company formed by the 1994 purchase of Grumman by Northrop. The company was the fourth-largest defense contractor in the world as of 2010, and the largest builder of naval vessels. Northrop Grumman employs over 75,000 people worldwide. Its 2010 annual revenue is reported at US$34 billion. Northrop Grumman ranks #72 on the 2011 Fortune 500 list of America's largest corporations and ranks in the top ten military-friendly employers. It has its headquarters in Falls Church, Virginia. Separate sectors, such as Aerospace Systems, produce aircraft for the US and other nations. The B-2 Spirit strategic bomber, the E-8C Joint STARS surveillance aircraft, the RQ-4 Global Hawk, and the T-38 Talon supersonic trainer, are used by the US Air Force. The US Army uses Northrop Grum