U.S. Air Force to unveil the 'most advanced military aircraft ever built' with cutting-edge stealth technology costing $2BN per jet

Full details about the bomber have been kept tightly under wraps, with next to nothing having been revealed about the aircraft. 

Photos of the plane haven't even been revealed at this point - only artist renderings of the aircraft revealed by the Air Force, and a teaser reel released by Northrup showing the shape of the B-21 hidden beneath a covering. 

The plane is said to utilize previously unseen stealth technology to avoid detection from enemies, and could be capable of flying with or without pilots, according to Defense One.  

A rendering of the B-21 Raider released by the US Air Force. The plane will be unveiled on Friday

A teaser for the unveiling of the B-21 Raider released by aerospace and technology contractor Northrop Grumman

Northrop President Tom Jones said the plane was 'optimized for operations in highly contested environments.'

The unveiling event on Friday will be by invitation only. Jones told Defense One the development project involved more than 8,000 people across 40 states. 

'I think it's the first view of what's going to be a great capability for our country,' he said.

The Air Force has called the B-21 a sixth-generation aircraft, meaning it would be the most advanced plane on the planet. 

Aircraft generations denote the major phases of flying technology. The fifth generation - which until the B-21 the world's most advanced warplanes are a part of - consists of technology that has predominated the 90s and early 21st century.

A rendering of the B-21 Raider released by Northrop Grumman. The warplane is expected to be the most advanced on Earth

The B-21 Raider will be unveiled at Northrop Grumman's Palmdale, California, facility, seen above with an earlier stealth bomber model

The Raider was named after a group of World War II bomber pilots and crewmen known as the Doolittle Raiders.

They consisted of 80 members of the Air Force who volunteered to attack Tokyo on April 18, 1942, mere months after Japan had attacked Pearl Harbor and brought the US into the war the previous December. 

The bombing raid was planned and led by Lieutenant Colonel James Doolittle and significantly boosted American morale.

The airmen carried out their attack from 16 B-25 bombers, which they launched from the flight deck of the USS Hornet despite the aircraft carrier not being designed to accommodate planes of such size.

'The raid acted as a catalyst to many future innovations in U.S. air superiority from land or sea,' Northrop wrote on its website. 'That bold, innovative and courageous spirit of the Doolittle Raiders has been the inspiration behind the name of America’s next-generation bomber, the B-21 Raider.' 

The B-21 Raider was named after a group of World War II bomber pilots and crewmen known as the Doolittle Raiders

The Dootlittle Raiders carried out their attack from 16 B-25 bombers, which they launched from the flight deck of the USS Hornet despite the aircraft carrier not being designed to accommodate planes of such size

The Doolittle Raiders consisted of 80 members of the Air Force who volunteered to attack Tokyo on April 18, 1942, mere months after Japan had attacked Pearl Harbor and brought the US into the war the previous December