The United States has presented a new bomber plane, almost invisible to radars. It was produced in complete secrecy and its introduction appears to come in response to the Pentagon's growing concerns about a possible conflict with China.
The last American bomber was produced 30 years ago. Almost every aspect of the program is secret. The planes are so secret that even when the news was announced Friday at an Air Force base in California, only artist drawings of it were released. The B-21 Raider is similar to the nuclear-capable bomber, the B-2 Spirit, which is likely to be phased out.
The new aircraft is part of the Pentagon's efforts to modernize its nuclear arsenal, which includes nuclear ballistic missiles and submarine-launched nuclear warheads. With this, the Pentagon is shifting from the counter-terrorism campaigns of recent decades to confront China's rapid military modernization.
By 2035, China is expected to secure 1,500 nuclear weapons. These military achievements, including cyber warfare, space capabilities and other areas, pose "the most significant and systemic challenge to US national security," the Pentagon said this week in its annual report on China.
"We needed a new bomber for the 21st century that would allow us to deal with much more complex threats, such as the threats we fear we will one day face from China and Russia," Deborah said. Lee James, the secretary of the Air Force when the B-21 Raider contract was announced in 2015.
"The B-21 Raider can handle these much more difficult threats."
While the Raider may resemble the B-2 predecessor from the outside, once you get inside, the similarities stop, said Kathy Warden, chief executive of Northrop Grumman, which is building the Raider.
"The way it works internally is extremely advanced compared to the 'B-2' because the technology has come so far," Ms Warden said.
Other changes could be the use of materials that enable the new aircraft to be harder to detect while having new ways to control electronic emissions. In this way, the Raider can fool enemy radars and disguise itself as another object, some defense analysts said.
In a document from the manufacturing company, "Northrop Grumman", it is said that "new production techniques and materials are being used to ensure that the 'B-21 Raider' defeats systems that prevent it from accessing the areas it is intended to go to".
Ms Warden could not discuss the details of these technologies, but said the new aircraft will be more difficult to detect on radar.
"When we talk about what is called low observability, it will be very low indeed. That means you'll hear the plane but you won't see it,” Ms Warden said.
Six B-21 Raiders are in production, while the Air Force plans to build 100 of them. They will carry nuclear weapons or conventional bombs and can be used with or without a human crew. The Air Force and Northrop also point to the relatively quick development of the Raider: The new plane was produced within seven years of the contract award, while other war products, including ships, have taken decades.
The cost of production is unknown. In 2010, the Air Force said the price to buy the 100 planes would cost an average of $550 million each, or roughly $753 million today, but it's unclear how much the Air Force is actually spending.
The fact that the price is not public worries government watchdogs.
"It can be a huge challenge for us to do our normal analysis of a major program like this," said Dan Grazier, senior defense policy fellow at the Project on Government Oversight.
"It's easy to say the B-21 Raider is on schedule without flight testing it yet. But only when one of them passes the actual testing phase are the real problems revealed. This is the point when the costs start to increase."
The Raider will not make its first flight until 2023.
However, using advanced computer programs Northrop Grumman has tested the capabilities of the 'Raider' using a digital twin, a virtual copy of the one presented on Friday.
The previous B-2 was projected to be a fleet of over 100 aircraft, but the Air Force ultimately settled on just 21 aircraft, due to cost overruns and a changed security environment following the collapse of the Soviet Union.
Additionally, not all B-2s are ready for daily use because of the aging aircraft's significant maintenance needs, said Todd Harrison, aerospace specialist and managing director at Metrea Strategic Insights. .
The new plane, the "B-21 Raider", took its name from the air attacks on the Japanese capital, Tokyo in 1942, known as the "Doolittle Raid".
It will be slightly smaller than the B-2 to increase its range, Ms Warden said.
In October 2001, the pilots of the old B-2 bomber set a new record when they flew for 44 hours straight to drop the first bombs on Afghanistan after the 9/11 attacks.
The B-2 often flies long round-trip missions because there are few hangars around the world that can accommodate its wingspan. This limits where the B-2 can land for necessary post-flight maintenance. In addition, hangars must be air-conditioned because the windows of older aircraft do not open and hotter climates can damage the electronic interior of the cabin.
The new aircraft will also have new hangars to accommodate its size and complexity, Ms Warden said.
A final change is the way the new bomber was introduced. While both were introduced at the same military base in California, the introduction of the earlier 'B-2' bomber was in 1988 with a public ceremony.
Given the advanced technology used to produce the camera and surveillance satellites, the unveiling of the new 'Raider' aircraft will take place in secret and inside a military facility. Guests, including Defense Secretary Lloyd Austin, will be on hand to open the doors to the facility to introduce the new aircraft, and then the doors will be closed again.