The US Air Force is set to unveil its secret stealth bomber, the B-21 Raider, a $639 million nuclear-capable jet able to sneak past Russian and Chinese sensors.

The advance bomber will be presented on Friday at 4:30pm PT in Palmdale, California, north of Los Angeles, and will enable the Air Force 'penetrate the toughest defenses for precision strikes anywhere in the world.' 

Built by aerospace and defense company Northrop Grumman, the B-21 Raider will be 'invisible' to enemy radar, capable of using Artificial Intelligence to connect to ally forces, feature 'digital bomb bay,' and eventually include an option to be completely remote. 

The B-21, which will cost $639 million per plane, is the first new US bomber in more than thirty years and will gradually replace the B-1 and B-2 aircrafts that first flew during the Cold War. 

Currently, six bombers are being built in Palmdale, which are expected to take flight in 2023. 

The Air Force and Northrop began developing the bomber in 2015 after company won the contract to design and produce the aircraft.

The B-21 will be the backbone of the future of the Air Force, and will be nuclear capable, able to be used for long-range strikes, surveillance and reconnaissance and electronic attacks. 

The B-21s are set to replace the B-52 aircraft that are already 60 years old, and the roughly 45 B-1 and 21 B-2 bombers.  

The Air Force plans to purchase at least 100 of the new stealth bombers.