Unveiled in December 2022, Northrop Grumman’s B-21 Raider represents the United States’ first new bomber in more than three decades and the anticipated linchpin of Air Force Global Strike Command’s modernized triad. Although visually similar to the B-2 Spirit, the Raider introduces numerous significant differences that make it the first sixth-generation bomber ever built.
A smaller profile, lower empty weight, and modular armament tailored to next-generation standoff weapons aim to improve survivability, lethality, and sustainment. Composite structures, advanced radar-absorbent materials, and open-mission systems promise fewer maintenance man-hours and faster software upgrades. Its efficient commercial-derivative engines will extend the unrefueled range beyond even that of the long-legged B-2.
General Thomas Bussiere, Commander of Air Force Global Strike Command, is quoted by Northrop Grumman on the homepage for the new bomber as saying:
“[The B-21] was developed with a combat lethality mindset, hand in glove with the engineers, acquisition professionals, and industry professionals that knew how to develop a capability so exquisite.”
In the following sections, we will identify each of the most prominent aspects that the B-2 and B-21 are different. Some are more easily identified than others. Every piece of the limited amount of public information we have on the new Raider paints a picture of a very different machine under its (radar-absorbent) skin.
Ultimate Flying Wing But Smaller
The B-21 will be about the same size as the B-2 according to an interesting observation based on both publicly released information and internet sleuths. The B-2 Spirit will remain the larger aircraft with a 172-foot wingspan and 69-foot length despite its similarity. The new B-21 Raider is estimated to span about 140-150 feet and have a length of roughly 60 feet. This is believed to be due to making the plane “thinner,” which trims radar cross-section, lowers gross weight, and allows the aircraft to use the same hardened shelters and runways as fighter wings.
The B-21’s empty mass is also lower, with a projected max gross weight between 240,000 and 260,000 pounds. The B-2 maximum takeoff weight (MTOW) is much higher at 336,500 pounds (152,634 kilograms). The lower requirements for payload allowed for a smaller and lighter airframe with less munitions capacity in exchange for upgrades to range and stealth.
This reduces the logistical burden for global deployments, resulting in fewer aerial tankers, lighter towing gear, and less ramp stress at expeditionary airfields. Crew space also shrinks, with the B-2 cockpit having two pilot stations as the B-21 did, but, famously, most can stand up to full height inside its flight deck. The cabin is tighter and optimized for autonomous operation, likely with provisions for single-pilot or unmanned modes.
New Shape: Stealth Minimalism
The unique “W”-shaped trailing edges of the B-2 will be a thing of the past, as the B-21 opted for a simpler triangle projecting rearward from the wing roots. The B-2’s semicircular “chevron” intakes are atop the wing, creating a blunt hump that reduces radar returns from the intricate S-ducts that feed its engines buried inside the plane’s skin. The B-21 has thin inlets blended more smoothly into its lifting-body design.
The paint is also a noticeable difference, as the B-2 sported a dark radar-absorbent material (RAM) paint scheme unlike the B-21. Advances in RAM paint are likely to lead to significant improvements in the long-term maintenance of the aircraft. That is on top of improvements in its ability to deflect radar and mask the plane’s other emissions such as heat, radio waves, and others.
The B-2 and its smaller stealth cousin, the F-22 Raptor, both experienced higher than anticipated paint needs over their lifespans. That diminishes readiness and raises sustainment costs, both of which the B-21 aims to reduce as the future fleet of Raiders will be relied on as the backbone of the strategic strike fleet.
Smaller Payload Than Before
The legacy B-2 can carry up to 40,000 pounds in two parallel bays, which can accommodate two 30,000-pound GBU-57 MOPs, 80 Mk-82 JDAMs, or 16 B61 or B83 nuclear bombs. Although its large bays take advantage of the jet’s span, the weight and drag are increased by the large doors, actuators, and rotary launchers. The Raider’s bays are deeper and narrower, with a combined capacity of 30,000 pounds. It makes up for its loss of brute force with a modular carriage that alternates between long-range standoff missiles and mixed racks.
The B-21 is built around next-generation weapons like the GBU-72 bunker buster, the AGM-181 Long-Range Stand-Off (LRSO) missile, and hypersonic attack weapons that are still in the development stage. While the Raider’s weapons control is more readily adaptable, which avoids costly retrofits and requalification that many legacy platforms, not just the B-2, have had to undergo.
The same is true for cruise missiles. The AGM-158 JASSM-ER and AGM-129 ACM, which are now outdated, are used on rotary launchers by the B-2. By integrating “side-by-side” palletized launch modules, the B-21 streamlines mechanisms and reduces release times by accepting larger diameter missiles without rotating out of the bay. This configuration also prepares the Raider for future cooperative weapons that require rectangular cross-sections that are incompatible with legacy rotaries, such as jammers, decoys, and swarming drones.
|
Metric |
||
|---|---|---|
|
RCS |
0.1 square meters |
0.01 square meters |
|
Payload |
40,000 pounds |
30,000 pounds |
|
Range |
6,000 nautical miles |
6,500 nautical miles |
|
Crew |
2 |
2 |
|
Flight hour cost |
$163,000 |
$95,000 (est.) |
|
Sustainment/year |
$41 million |
$25 million (est.) |
The B-2 underwent seven years of testing before going into operational nuclear alert in 1997. The Air Force intends to use digital twin models, which enable engineers to virtually verify carriage, interface, and ballistic performance, to certify the B-21 much earlier than it would be put into service. Because the Raider can assume deterrence roles more quickly due to shorter certification cycles, the B-1B can be retired earlier and fewer B-52 sorties for nuclear assurance missions can be conducted.
New Powerplants For The Raider
The B-2 relies on four F118-GE-100 non-afterburning turbofans, each providing 17,300 pounds of thrust. These engines, derivative of the F110 fighter core, were reliable but thirsty. The B-21 is believed to employ two, possibly three, commercially derivative turbofan engines, also non-afterburning. Fewer, more efficient engines cut maintenance tasks by half and bring the benefits of more modern power plants with higher bypass ratios.
The redesign will improve thermal signatures and likely reduce engine noise as well. With their intricate exhaust ducts shielded with cutting-edge composites, the Raider’s engines are buried deeper in the wing. These materials reduce infrared contrast against a freezing high-altitude sky even better than the B-2.
More Tech In A Smaller Package
Raider debuts electronically scanned radar and advanced electronic warfare (EW) capacity. No GPS needed on the B-21 when the Raider sorties into GNSS-denied environments. The EW systems are said to be related to the Lockheed Martin F-35’s ASQ-239. Alongside the bleeding-edge tech on the B-21 are as many commercial-off-the-shelf (COTS) parts as possible to reduce maintenance risk and cost, as Aviationweek reported.
The plan is also envisioned as a platform for both solo missions into extremely hostile battle spaces and a central pillar of the “system of systems” in the Air Force of the Future (AFOTF). The USAF vision for the next era is a combination of unmanned drones alongside manned “exquisite” platforms that leverage the qualities of both expendable aircraft and high-value assets.
After the delivery of the second B-21 Raider for testing, Air Force Chief of Staff General David Allvin remarked:
“The B-21 Raider program represents a cornerstone of our strategic nuclear modernization. The concurrent efforts in testing, sustainment preparation and infrastructure investments clearly illustrate our commitment to providing unmatched capabilities to deter and defeat threats well into the future.”
The B-21 is built on the Air Force’s Open Mission Systems (OMS) standard, running the latest software on more powerful processors. New sensors and programs for cyber defense, data fusion, or artificial intelligence (AI) can be fielded via secure uploads. The legacy B-2 updates typically required months-long depot modifications and exhaustive validation processes for every upgrade.
Ultra Ultra Long Range
The USAF has reportedly focused more on maximizing range more in the B-21 than it did during the development of the B-2. Despite carrying less fuel, rough figures suggest 120,000 pounds internally versus the B-2’s 167,000. The B-21 is expected to exceed the Spirit’s 6,000-nautical-mile unrefueled range thanks to improved aerodynamics and engines.
Digital design tools optimized the Raider’s laminar flow and subsonic lift-to-drag ratio, yielding cruise efficiencies near 25% better. When aerial refueling is considered, both aircraft circle the globe, but the B-21 will require fewer tanker rendezvous, reducing vulnerability and increasing both the efficiency and flexibility of mission tasking.
Only three permanent US locations can currently host the B-2 due to practical news and security control constraints. The Raider’s smaller footprint and simpler operational needs will let it disperse to more airfields in shooting war, complicating adversary targeting. Add to that a projected mission-capable rate above 80% (versus the B-2’s historical 50-60%) and commanders gain more available tails for simultaneous nuclear deterrence, conventional strike, and intelligence missions across multiple theaters.
