As photographs of the first “two” U.S. Air Force B-21 Raider bombers blast onto the public scene, most observers can only speculate about the mysterious, yet paradigm-changing suite of technologies said to be woven into the platform.
By design, there is very little information available about the platform’s critical technical elements that are less visible to the observer.
Artist rendering of a B-21 Raider in a hangar at Ellsworth Air Force Base, South Dakota, one of the future bases to host the new airframe. AFCEC is leading a $1 billion construction effort at Ellsworth to deliver sustainable infrastructure to meet warfighter demands for bomber airpower. (U.S. Air Force graphic)
B-21 Raider Up Close. Image Credit: U.S. Air Force.
Its weapons interfaces, computing, coating materials, stealth components, thermal management, and networking technologies are expected to introduce new, game-changing capabilities into the realm of high-altitude stealth bombing.
Is the B-21 Stealthier Than the B-2?
What is visible to the eye, when one compares available B-21 images to those of the existing B-2, does seem to indicate interesting advances in the realm of stealth.
Compared with the B-2, the B-21 has a smoother, more wing-body-blended horizontal fuselage with smaller, more conformal inlets on top of each wing.
Perhaps even more significant, the aircraft itself is considerably smaller and lighter than its B-2 predecessor.
Specifically, the wingspan of the B-2 is 172 feet, considerably longer than the 140-foot wingspan of the B-21.
There is a huge difference in take-off weight as well; the B-2 is cited with a maximum take-off weight of 336,500 pounds, much more than the cited 260,000-pound take-off weight of the B-21.
Smaller size and technological sophistication are by no means incompatible; rather, they are somewhat aligned, given technological advances in recent years.
Why is the B-21 so much smaller? Many of the reasons likely pertain to weight, speed, and drag, as a lighter-weight aircraft would be capable of sustaining advanced speeds with less fuel and drag, and a smaller airframe would also better enable aerial agility.
Certainly, a high altitude bomber would not need to dogfight and “vector” like a fighter jet, yet there is definitely a tactical advantage to a bomber having improved aerial agility.
The B-21 Raider is designed with an open systems architecture, enabling rapid insertion of mature technologies and allowing the aircraft to be effective as threats evolve. The bomber was designed up front for supportability and maintainability-based upon decades of lessons learned and best practices from prior aircraft programs-to improve long-term affordability and outcomes in operations and sustainment. The B-21 first flight is anticipated to take place in calendar year 2023. (U.S. Air Force photo)
A second B-21 Raider test aircraft takes off, Sept. 11, from Palmdale, Calif., to join the Air Force’s flight test campaign at Edwards Air Force Base, Calif. The addition of the second test aircraft expands mission systems and weapons integration testing, advancing the program toward operational readiness. (Courtesy photo)
A B-21 Raider conducts flight tests, which includes ground testing, taxiing, and flying operations, at Edwards Air Force Base, California, where it continues to make progress toward becoming the backbone of the U.S. Air Force bomber fleet. The B-21 will possess the range, access, and payload to penetrate the most highly-contested threat environments and hold any target around the globe at risk. The B-21 program is on track to deliver aircraft in the mid-2020s to Ellsworth Air Force Base, South Dakota, which will be the first B-21 main operating base and location for the B-21 formal training unit. (Courtesy photo)
Speed alone is a survivability-enhancing attribute for a high-altitude stealth bomber, as it makes the aircraft even less “detectable” to ground-based radar systems. Additionally, a high-altitude bomber would greatly benefit from increased maneuverability in a hostile, high-threat environment, as targets and combat circumstances change quickly.
It is also entirely conceivable that a smaller aircraft would, quite simply, be stealthier as well. Not only is there less “airframe” or “metal” for ground-based radar to bounce electromagnetic “pings” off of and generate a return signal, but a smaller aircraft might generate less of a heat signature.
It seems technologically sensible that a smaller airframe, such as the B-21, might leverage a new generation of thermal management technology. The closer an airframe is to the temperature of the surrounding atmosphere, the less detectable it is to infrared “heat” sensors.
B-21 Computing Advances
The primary reason the B-21 is smaller than the B-2 may be advances in software, AI-enabled computing, and hardware configurations. “Lowering the hardware footprint,” as it is called, refers to how advances in software, virtualization, storage, and processing capacity enable a smaller hardware “form factor.”
This increases efficiency and allows a smaller platform to accomplish as much or more sensing, computing, networking, and data processing as a larger one.
This form-factor dynamic is not only relevant to computing but also to sensing technologies and weaponry.
Fewer pieces of hardware are needed when smaller components can combine the functionality of a group of otherwise disconnected sensors into a single integrated system.
Essentially, technological progress can enable superior sensing, computing, and weapons interfaces in a smaller airframe.
This kind of streamlined sensing and computing closely aligns with the aircraft’s stated concepts of operation.
The B-21 has been described by senior Pentagon weapons developers as a “sensing” node and a flying command-and-control platform capable of operating groups of drones and sharing information across land, air, sea, and space domains.
The bomber will not only conduct bombing missions but also function as a sensing and targeting aircraft capable of exchanging and organizing time-sensitive information from satellites, drones, manned aircraft, ground vehicles, and even surface ships.
About the Author: Kris Osborn, President of Warrior Maven
Kris Osborn is the President of Warrior Maven – Center for Military Modernization. Osborn previously served at the Pentagon as a highly qualified expert in the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Masters Degree in Comparative Literature from Columbia University.
