??B - 2 Bomber (English: B - 2 Stealth and Strategic 'bomber, nickname: Spirit, the Spirit, known as: Northrop Grumman gave B - 2 Stealth Strategic bombers), is made up of Northrop (Northrop Grumman) and the Boeing company jointly developed by the Massachusetts institute of technology for the U.S. air force performs the task of Strategic nuclear/conventional strike low detection can be flying wing Bomber. B-2 bomber is the only stealth strategic bomber in the world today. Its main feature is low detectability, which is commonly known as stealth capability. It can be safely attacked through a tight air defense system. B-2's stealth is not limited to radar detection, but also includes the reduction of infrared, visible and noise signals, so as to minimize the possibility of detection and locking. The b-2 has a range of 12,000 km without refueling in the air and 18,000 km at a time. Each mission typically takes no less than 10 hours to fly in the air, and the air force says it has "global reach" and "global destruction" capabilities. The stealth capability of the b-2 is comparable to that of the smaller f-117, while the operational capability is similar to that of the larger b-1b. In 1997, the first six b-2 bombers came into service, producing only 21. The b-2, which costs $2.4 billion each, is two to three times more expensive by weight than gold at the time of service.Strategic