Summary and Key Points You Need to Know on B-21 Bomber: The B-21 Raider is set to replace the B-2 Spirit, a revolutionary stealth bomber, with significantly enhanced stealth capabilities. Developed by Northrop Grumman, the B-21 is designed to penetrate sophisticated anti-access/area denial (A2/AD) defenses, boasting an extremely low radar cross section (RCS).

-Some experts claim the B-21 could have an RCS as small as an insect’s. The bomber is undergoing flight tests, with limited details about its capabilities.

Bottomline: However, its design closely mirrors the B-2, featuring a flying-wing structure with advanced avionics and stealth refinements that make it more effective in evading detection than its predecessor.

The B-21 Raider is slated to replace the B-2 Spirit, which was itself a game-changing stealth platform. But the B-2 is a generation-old, and aerospace designers have been refining their stealth capabilities in the thirty years since the B-2 was developed.

The B-21 promises to be the culmination of those stealth refining efforts, with some claiming that the new stealth bomber will have the radar cross section (RCS) of an insect. While the claim – that a large, fuel-guzzling military aircraft could have the RCS of a honeybee – seems hyperbolic, one Washington thinktank is backing the claim, and urging the US to pursue large-scale acquisition of the B-21.

How Stealthy Is the New B-21?

“The multi-author paper from the Hudson Institute stresses the strategic deterrence potential of the Northrop Grumman B-21 based on its ability to penetrate the most sophisticated anti-access-area denial (A2/AD) defenses, its long range and flexibility,” Forbes reported.

The bit about being able to penetrate the most sophisticated A2/AD defenses is oblique, technical jargon for: the B-21 is extremely stealth aka has a miniscule RCS. So, whereas a non-stealth airframe, with a relatively large RCS, would not be able to penetrate even rudimentary A2/AD defenses, an airframe capable of penetrating sophisticated A2/AD defenses is impliedly very stealth (low RCS).

The ever-increasing sophistication of A2/AD defenses is what has necessitated the reciprocating increase in stealth sophistication. Air space is getting harder to penetrate. Airframes with smaller RCS signatures are becoming required to penetrate those air spaces.

Fourth-generation fighters like the F-15 and F-16 are relatively useless against sophisticated adversaries with A2/AD systems in place, meaning the fourth-generation fighters would be relegated to defensive roles only in a modern conflict.

Even the B-2, which debuted as the world’s first stealth bomber and forced America’s enemies to make geopolitical recalculations to account for the fact that there was now a nuclear-armed bomber that could move about unseen, has lost its stealth edge; the B-2’s exact stealth measurements are not public information, but one can presume that at least part of the Air Force’s impetus in replacing the $2-billion-per-unit B-2 bomber was because the B-2 could no longer penetrate air space as smoothly as it once could.

What Will the B-21 Raider Be Capable of?

Not a whole lot is known about the B-21. The new bomber is undergoing initial flight testing, we know that, but for the most part, the program is cloaked in secrecy. The most telling disclosure that the program has offered is a set of pictures.

The pictures show an airframe that looks almost like a carbon copy of the B-2 – a flying wing. Presumably, if one were to dig into the granular details of the airframe, the B-21 would feature subtle changes from the B-2 – changes that lower the RCS relative to the ageing B-2. And presumably, if one were to peak under the hood, they would find upgraded hardware, computer and avionic systems that were befitting a twenty-first-century weapons project.

About the Author: Harrison Kass 

Harrison Kass is a defense and national security writer with over 1,000 total pieces on issues involving global affairs. An attorney, pilot, guitarist, and minor pro hockey player, Harrison joined the US Air Force as a Pilot Trainee but was medically discharged. Harrison holds a BA from Lake Forest College, a JD from the University of Oregon, and an MA from New York University. Harrison listens to Dokken.

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