According to foreign media reports, the US Air Force recently released a video of the next generation strategic bomber B-21 "Raider" conducting flight tests at Edwards Air Force Base in California, and confirmed the addition of two new B-21 bomber deployment bases. According to reports, after the B-21 bomber officially enters service, it will gradually replace several other bombers and become the main force for the US Air Force to build global strike capabilities. Rapid production has attracted attention. The US Air Force first proposed the B-21 bomber project in 2012, which was then known as the LRS-B bomber; In 2015, the project was officially named the B-21 bomber and developed by the American company Northrop Grumman. In March 2022, the US Air Force conducted ground tests on the first B-21 bomber; In November 2023, the B-21 bomber made its first test flight at Factory 42 in Palmdale, California; In January 2024, just two months after its maiden flight, the US Department of Defense announced that the B-21 bomber had entered the low-speed production phase. According to reports, the US Air Force stated in the release of relevant flight test videos that two B-21 bombers successfully completed ground static tests in a simulated environment, proving that the digital modeling technology of B-21 bombers has high accuracy. In addition, Northrop Grumman is conducting follow-up system testing, including researching how to expand the operational range of the bomber. The CEO of the company's aviation system, Jones, stated that the B-21 bomber is currently undergoing flight tests twice a week, and in the future, the flight frequency may be increased to once a day to efficiently and quickly verify various flight performance indicators of the bomber. It is reported that the US Air Force has applied for $5.34 billion in the 2025 fiscal year budget to accelerate the production of B-21 bombers, achieving the goal of receiving the first aircraft of this type in 2025 and forming combat capability by 2030. The overall design of the B-21 bomber is relatively advanced. In terms of appearance, it adopts the wing design of the B-2 bomber, but the protruding parts of the fuselage have been rearranged to further reduce the radar reflection area. Among them, the engine compartment is smoothly connected to the fuselage without obvious bulges; The intake duct adopts a sunken design, embedded in the cabin, which is not easily detected by radar and can improve the stealth effect. In terms of combat positioning, due to the reconnaissance, surveillance, electronic attack, and communication relay capabilities of the B-21 bomber, the US Air Force has clarified that this type of bomber will perform "penetrating air superiority" missions in future high threat battlefield environments. It can break through the opponent's air defense system, use weapons inside and outside the defense zone to gain air superiority, and assist fighter jets, electronic warfare aircraft, and reconnaissance aircraft in implementing diversified breakthroughs. At the same time, it has stronger situational awareness and complex data processing capabilities, which can improve the probability of survival on the battlefield. In addition, the development speed of the B-21 bomber has attracted attention. It is reported that the B-21 bomber uses digital simulation and digital twin technology throughout the design, testing, and assembly process, greatly improving development efficiency. At the same time, Northrop Grumman has cancelled the previous model of developing "prototypes" before developing new aircraft. Officials from the US Department of Defense stated that the six experimental B-21 bombers will follow the same manufacturing process as the formal production aircraft and will be transferred to the US Air Force as part of the first batch of B-21 bombers after the testing mission is completed to save time and costs. In a January report on the US Theater News website, the Deputy Secretary of Defense Procurement and Maintenance, William Lapland, was quoted as saying, "The key feature of the B-21 bomber project is rapid large-scale production from the beginning. If it cannot be rapidly produced and deployed to combat units, then air deterrence will be impossible." In order to achieve the so-called "rapid large-scale deployment," the US Air Force is accelerating the production of B-21 bombers while other related actions are also being pushed forward. Continuously announcing deployment bases. It is reported that the US Air Force announced in November 2023 that the first B-21 bomber squadron would be deployed at Ellsworth Air Force Base in South Dakota, and recently announced that B-21 bomber squadrons would also be deployed at Whiteman Air Force Base in Missouri and Deiss Air Force Base in Texas in the future. According to sources from the US Air Force, staff from Northrop Grumman have been stationed at the aforementioned base to upgrade and modify existing facilities and equipment. The 2nd, 5th, and 509th bomber squadrons also selected personnel for training to prepare for the rapid deployment of B-21 bombers after receiving them. The above three bases are also the main deployment sites for the current active strategic bombers of the US Air Force. Equipped with multiple advanced weapons. The B-21 bomber has both nuclear and conventional attack capabilities. In addition to carrying all types of weapons and ammunition from the B-2 bomber, the US Department of Defense also equips it with multiple advanced weapons, including long-range cruise missiles and new nuclear bombs. The former, such as the AGM-158XR cruise missile, has an armor piercing warhead weighing about 453 kilograms and a range of nearly 1800 kilometers; The latter is the B61-13 new nuclear bomb, which adopts a "GPS+inertial guidance" composite guidance method, and is equipped with a spin rocket engine on the body. Its strike accuracy is better than 30 meters, and its explosive yield is 360000 tons, breaking the upper limit of 100000 tons for tactical nuclear weapons. Collaborative drone operations. The report states that the US Air Force plans to equip B-21 bombers with unmanned aerial vehicles for coordinated operations, creating a new type of manned/unmanned combat formation. Regarding the equipped drone models, sources say that the US Air Force is considering the latest RQ-180 stealth long endurance drone. It should be pointed out that the B-21 bomber project took only 9 years from development to production, and its ultra short development cycle has raised many questions. Industry insiders say that currently, most countries around the world are developing military aircraft through a process of "technical validation aircraft prototype aircraft pre production aircraft mass production", and continuously adjusting based on the data generated by this process. However, in order to save time, the B-21 bomber relied on digital engineering technology throughout its development process. Without a prototype, six pre production aircraft were directly developed, resulting in the bomber being put into production while some systems were still under development. This mode of simultaneous test flight, research and development, and production may lead to unforeseen technical issues, ultimately delaying project delivery time. (New Society)