The U.S. Air Force is moving forward with plans for a top-secret next generation bomber that could one day fly without a pilot.
Spending on the project has topped a billion dollars this year alone - and companies vying to win a contract to build the bombers are already said to have built either full-scale or miniature prototypes and tested them in wind tunnels.
Spending on the long range bomber was $200 million in 2012.
A billion dollars has been spent in 2015.
Spending could increase to $3 billion in 2018.
100 brand-new bombers will hopefully cost as $55 billion in total. They will replace 1960s-vintage B-52s and B-1s from the ’80s.