The US' newest high-tech nuclear stealth bomber has made its debut after years of secret development.
The B-21 raider, which will be able to deliver both conventional and nuclear weapons around the world using long-range and mid-air refuelling capabilities, is part of the Pentagon's answer to rising concerns over a future conflict with China.
It is the first new US bomber aircraft in more than 30 years.
The bomber was unveiled at an event at the US Air Force's Plant 42 in Palmdale, California where six aircraft are already at various stages of assembly.
US defence secretary Lloyd Austin said: "This isn't just another airplane.
"It's the embodiment of America's determination to defend the republic that we all love…We will soon fly this aircraft, test it, and then move it into production".
Each aircraft, which carries a similar 'flying wing' shape to its predecessor, the B-2, is projected to cost roughly $729.25m.
The Air Force planned to buy at least 100 of the planes and begin to replace B-1 and B-2 bombers. Almost every aspect of the programme is classified.
The aircraft is part of the Pentagon's efforts to modernise all three legs of its nuclear triad - which includes silo-launched nuclear ballistic missiles and submarine-launched warheads, as it shifts from the counterterrorism campaigns of recent decades to meet China's rapid military modernisation.
China is on track to have 1,500 nuclear weapons by 2035.
The Pentagon said this week in its annual China report that Beijing's gains in hypersonics, cyber warfare and space capabilities present "the most consequential and systemic challenge to US national security and the free and open international system".
Deborah Lee James, the Air Force secretary when the Raider contract was announced in 2015, said: "We needed a new bomber for the 21st Century that would allow us to take on much more complicated threats, like the threats that we fear we would one day face from China, Russia".
Kathy Warden, chief executive of Northrop Grumman Corp., which is building the bomber, said the B-21 is "extremely advanced" compared to the B-2 with advances in computer capabilities and materials used in coatings which make it "harder to detect".
Several defence analysts say other advances include new ways to control electronic emissions - meaning the bomber could confuse adversary radars and disguise itself as another object.