The Northrop Grumman's B-2 Spirit (also known as the Flying Wing or more commonly as the stealth bomber) is an American heavy bomber with "low observable" stealth technology designed to penetrate dense anti-aircraft defenses and deploy both conventional and nuclear weapons. Because of its considerable capital and operations costs, the project was controversial in Congress and among Pentagon brass. During the late 1980s and early 1990s, Congress slashed initial plans to purchase 132 bombers to just 21.