The Math Problem: The U.S. Air Force’s B-21 Raider is set to replace aging bombers, but experts argue 100 units may not be enough.
Key Points and Summary: With China developing its H-20 stealth bomber and rising threats from Russia, military analysts and think tanks suggest the U.S. may need 200–288 B-21s.
Artist rendering of a B-21 Raider concept in a hangar at Dyess, Air Force Base, Texas, one of the future bases to host the new airframe. (Courtesy photo by Northrop Grumman)
-The Raider’s advanced stealth, open-architecture systems, and long-range strike capabilities make it a key asset for future warfare.
-However, scaling up production would require additional manufacturing partners and facilities.
-As global tensions rise, the question remains: will the Pentagon expand its bomber fleet before it’s too late?
B-21 Raider: Is More Than 100 Possible?
The Northrop B-21 made its first flight on November 10, 2023. It was one of the significant steps to the airframe entering service close to 2030. The original procurement of the aircraft is planned for 100 units, which would provide the US Air Force with its first stealth bomber ever to be available in large numbers. The service’s previous stealth long-range attack platform was the B-2, of which only 21 units were produced.
The B-21 aircraft’s larger production order is of interest to the United States Air Force in several aspects. One of the first on the list is that it is a smaller and more versatile platform, according to a list of very detailed design requirements. The short list of the aircraft’s advantages over other previous bomber aircraft are:
Expanded Payload options: The B-21 Raider can carry both conventional and nuclear weapons and would be used in theatre-level operations and not just as a strategic strike weapon.
Extended reach: The B-21 can reach distances and is more forward deployable than the older, larger B-2.
Open-architecture systems: The B-21’s onboard systems are based on a digital infrastructure that can be easily updated to support new weapons and equipment.
Advanced maintenance features: The B-21 is designed to be cost-effective and deployable over an extended service life. The expectation is that a workhorse or utility strike aircraft can be pressed into service and supported in austere environments.
Low-radar cross-section design: The B-21 Raider has advanced stealth-driven design aspects to make it less detectable to enemy air defense systems.
PLAAF Challenge
The B-21 was under development for some time with the knowledge that the PRC was developing a comparable aircraft at its Xi’an Aerospace Corporation (XAC), the H-20 program. The B-21 was previously intended to neutralize China’s People’s Liberation Army Air Force (PLAAF) fielding that aircraft and to be boosted by the support of unmanned “loyal wingman” aircraft. However, work on developing that unmanned aircraft concept was canceled in July 2022.
An artist illustration depicts a U.S. Air Force extended-range B-21 Raider escorted on a mission by armed unmanned next generation air dominance platforms. This fictional bomber features longer, wider wings, and a deeper fuselage that accommodates larger fuel tanks and dual weapons bays that enables the bomber to carry a much larger and varied payload. Mike Tsukamoto/staff; Greg Davis/USAF
The previous US Secretary of the Air Force, Frank Kendall, had in the past talked about “being open about looking at the various options they have for increasing their force size, and has talked specifically about NGAD, and we know that B-21 is in the mix, as well.”
That statement was in reference to numerous operational concepts examined for the employment of the B-21 in conjunction with the NGAD (Next Generation Air Dominance) sixth-generation fighter program. However, that program’s status is a major question mark over the issues of widely divergent projected costs.
Previous statements by Kendall have presented possibilities that the NGAD could cost in the hundreds of millions per unit. At other times, he has called for the next major US fighter to be priced even lower than the F-35.
The latter objective would be a significant challenge. Economies of scale of the variants of the F-35 aircraft, which is being procured in numbers exceeding 1,000, permit a much lower per-unit price tag than anything in the range of projected numbers for the B-21, which is currently around 100.
B-21 Raider. Image: U.S. Air Force
Proposals for the B-21 to be built in far greater numbers than the original 100 ordered are prompted by projected future conflict scenarios. Specifically, this is the need to strike and neutralize an extensive and dispersed portfolio of targets in the event of war. These would be sites deep inside Chinese and Russian airspace, which a B-21 fleet of only 100 bombers would be unable to address adequately.
A report authored in June 2020 by former US bomber pilot Mark Gunzinger at the Melbourne-based Mitchell Institute think-thank called for a fleet of more than 200 B-21s. Another 2019 US Congressional Research Service (CRS) report highlighted that retirement of the B-1B, B-2, and eventually the B-52 bombers would require much larger B-21 acquisitions to avoid a collapse in the size of the overall bomber fleet.
The largest of the advocated “re-thinks” of the B-21 force came from the Washington D.C.-based Centre for Strategic and Budgetary Assessments. That study called for the acquisition of 288 B-21 bombers and the retention of the entire B-52H fleet.
B-21 Raider. Image Credit: U.S. Air Force.
In order for these numbers to be realized, industrial partners in the form of other OEMs would likely be required to enter the production phase of the effort. More likely than not, parts of such a sizeable B-21 fleet would have to be manufactured in several locations and then shipped to final assembly points.
This is likely the only scenario that could see enough aircraft to be built before significant retirements, requiring older bombers to be withdrawn from service.
About the Author: Reuben F. Johnson
Reuben F. Johnson is a survivor of the February 2022 Russian invasion of Ukraine and is now an Expert on Foreign Military Affairs with the Fundacja im. Kazimierza Pułaskiego in Warsaw. He has been a consultant to the Pentagon, several NATO governments and the Australian government in the fields of defense technology and weapon systems design. Over the past 30 years he has resided in and reported from Russia, Ukraine, Poland, Brazil, the People’s Republic of China and Australia.
