The B-52 Stratofortress is a long-range strategic bomber that has been operated by the United States Air Force since the 1950s. It can carry up to 70,000 pounds of weapons and has an estimated cost of $123 million USD. Development of the program cost $100 million in 1955, which is equivalent to $1.14 billion adjusted for inflation. The current strategic bomber upgrade is estimated to cost $11.8 billion. The total cost of the B-52 CERP Middle Tier of Acquisition effort will be $1.32 billion, including research and development costs. The B-52 is also known for being the world's largest bomber.