The B-2 Spirit was developed by the Air Force as a replacement for the aging B-52 bomber fleet. This long range stealth bomber is designed for strategic penetration. The boomerang shape and radar absorbing paint make it difficult to detect radar. It has a range of over 6,000 nautical miles. Armaments include bombs, both nuclear and conventional, as well as rotary launchers. It is the most expensive military aircraft ever produced with an approximate unit cost of 2.4 Billion.