The US Air Force's B-2 Spirit stealth bomber. Image: X Screengrab

The US has upgraded its legacy B-2 Spirit stealth bombers with cutting-edge software, slashing update times and supercharging combat readiness against near-peer adversaries.

The move comes amid potential production shortfalls in the next-generation B-21 Raider stealth bomber program under development for the US Air Force by private contractor Northrop Grumman.

This month, Air & Space Forces Magazine reported that the US Air Force has upgraded its B-2 stealth bomber with a new open missions systems (OMS) software capability along with additional enhancements.

The report says the upgrade, dubbed Spirit Realm 1 (SR 1), was developed through collaboration between the Air Force Global Strike Command and the B-2 Systems Program Office and aims to keep the bomber relevant and credible until the B-21 is operational.

The agile software development process adopted for the B-2 has dramatically reduced the time required for software updates, now taking less than three months compared to the previous two-year cycle. That, in turn, allows for quicker integration of new weapons and continuous software improvements, directly enhancing combat capability.

Air & Space Forces Magazine mentions that the OMS architecture streamlines software updates and improves the bomber’s interoperability with other systems. It also says the upgrade includes better displays, flight hardware and survivability enhancements.

The same report notes that the B-2 fleet, now numbering 19 aircraft following two crashes, remains the US Air Force’s only penetrating aircraft until the B-21s reach initial operational capability at Ellsworth Air Force Base. It also notes that the B-21’s initial operational capability (IOC) timeline is still undisclosed.

As for further B-2 weapons and hardware upgrades, Asia Times reported in September 2022 that the US deployed the Joint Air-to-Surface Standoff Missile-Extended Range (JASSM-ER) from a B-2 stealth bomber, potentially serving in a new anti-ship role in the Pacific.

This capability significantly enhances the aircraft’s ability to strike targets at any location, at any time, and greatly extends the range of the cruise missile.

The B-2 can carry up to 16 JASSM missiles, including the extended-range JASSM-ER variant. Thanks to enhanced fuel capacity and a more efficient turbofan engine, the JASSM-ER variant has a range of 965 kilometers, compared to the original version’s 400-kilometer range.

The modernization of crypto technology aims to enhance the security of communication for high-frequency transmissions, enabling secure communication devices in potential future threat scenarios. The Radar Aided Targeting System (RATS) upgrade will also allow the B-2 bomber to utilize the B61 Mod 12 nuclear bomb for nuclear strike missions where GPS is unavailable.

Combining the B-2 stealth bomber with the JASSM-ER cruise missile is expected to give the US an advantage in overcoming modern air defenses, potentially reducing risks for bomber crews in anti-access/area denial (A2/AD) environments.

The B-21 boasts several advantages over the 1980s B-2, with the former being smaller, sleeker, stealthier and future-proofed with open systems architecture. However, given China’s rapid military modernization and B-21 production problems, the US may not have enough B-21s for a Taiwan campaign, forcing the US to keep the B-2 in service longer than anticipated.

In a March 2023 report for the Mitchell Institute for Aerospace Studies, Mark Gunzinger says that a 300-plus bomber force with at least 225 penetrating B-21s is needed for the capacity to sustain overwhelming strikes to attack highly mobile enemy forces in an invasion of Taiwan and deter opportunistic aggression in another theater.

Gunzinger notes that a full-scale B-21 production rate of 20 per year or more is critical for deterring China, whose military modernization campaign is on track to prepare it for a campaign to seize Taiwan by 2027.

However, in an article this month for The National Interest (TNI), Maya Carlin mentions that plans to build 300 B-21s over the next decade with a production rate of just 10 aircraft per year at US$750 million each may not be enough to deter US near-peer adversaries.

Carlin says that B-21 production shortfalls are attributable to US budget issues rather than Northrop Grumman’s production limitations. She also says that while US fighter aircraft shortfalls can be offset by unmanned Collaborative Combat Aircraft (CCA), that approach does not apply to the B-21 bomber.

Asia Times pointed out in June 2024 that while the US Air Force anticipates having 24 to 30 B-21s operational by the early 2030s, with a production rate of up to 10 aircraft per year, that production rate is lower than the 20 aircraft per year for older bombers like the B-52 and B-1. This situation may lead to a potential shortage of B-21 aircraft for a Taiwan conflict.

As for how the US may use upgraded B-2s and B-21s in a Taiwan war with China, Megan Tonner-Robinson and other writers note in a January 2022 article for Wild Blue Yonder (WBY) that the large quantity of fighter aircraft and integrated air defense systems in an A2/AD environment makes a traditional assault from US fighter and strike aircraft impractical.

Tonner-Robinson and others say that the advanced technology of US stealth bombers like the B-2 and B-21 may enable them to evade China’s A2/AD systems and effectively target critical areas on the mainland, disrupting crucial infrastructure such as command centers, runways, fuel depots and power grids.

They mention that destroying the A2/AD system’s parts creates pockets of vulnerability for US fifth-generation and fourth-generation fighters to exploit and attack. They note that the fight in the air would be a battle of attrition, with victory going to the side that can last the longest in the air.

However, Tonner-Robinson and others say that combining stealth attacks, long-range cruise missile strikes, suppression of enemy air defense (SEAD) and cyber warfare could shift control of the airspace in favor of the US.

In addition to their deep penetration conventional strike roles, the B-2 and B-21 are slated to become cornerstones of the US air-based nuclear deterrent, with the upgraded B-2 supplementing the next-gen B-21.

In a December 2023 Hudson Institute report, Rebeccah Heinrichs and other writers say that the B-21’s flexibility and extended range make it essential for holding at risk the growing number of Chinese and Russian conventional and strategic weapons, key facilities and other objects hidden deep in their territories.

Heinrichs and others mention that the bombers’ tremendous warfighting potential against highly sophisticated defenses ensures the credibility of US deterrence.

They note that the B-21 bomber fleet can offer both conventional and nuclear deterrence in various regions, ensuring US support for allies and deterring potential adversaries while demonstrating the US’s commitment to global security.

Heinrichs and others point out that the B‑21’s operating and sustainment costs are similar to those of other manned aircraft, and increasing the fleet size beyond 100 would decrease the costs per plane.

They recommend that the US plan to acquire at least double the original number of B‑21 bombers to deter near-peer adversaries and effectively engage in potential conflicts.

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3 Comments

  1. Who says there is going to be a Taiwan war? Is US only problem solving strategy war? Taiwan would end up in shambles, and for what?

  2. Stealth aircraft can be detected with High-Frequency (HF) band radar. The wavelengths are long enough to penetrate the stealth coating and reflect off metal parts in the interior. When the USAF was flying the F-117—the one that looks like it is made of prisms—it showed up on Australia’s Jindalee over-the-horizon radar the size of a 737.