Inside months of the Cuban Missile Disaster, weapons designers at Los Alamos Nationwide Laboratory started engineering what would turn out to be the longest-serving and most adaptable weapon in America’s nuclear arsenal. Though it was ballistic missiles that had sparked the disaster in Cuba and got here to represent the nuclear age, the brand new B61 could be an air-delivered gravity bomb. So named as a result of it’s dropped from an plane, gravity bombs had been a characteristic of aerial warfare since picket biplanes launched them over the trenches in World Battle I. However the B61 was a revolutionary weapon, that includes a versatility not seen in a nuclear munition earlier than or since.
Sixty years later, it stays the first household of gravity bombs within the U.S. nuclear stockpile. The B61’s longevity attests to each the timelessness of its function and the modularity of its authentic design. Certainly, there isn’t a longer a single B61 as we speak however an ensemble of weapon programs that each one derive from the identical progenitor. 13 variants, or modifications, have been developed, every with distinct traits and missions. Quite a lot of modifications could be delivered by a broad vary of U.S. and allied plane, from strategic platforms just like the B-2 stealth bomber to dual-capable fighters such because the F-15, F-16, F-35, and the European Twister, in addition to next-generation programs just like the B-21 Raider. In varied configurations, the bombs could be launched in free-fall mode or with a speed-retarding parachute that when packed is denser than hardwood.
The most recent descendant on this bloodline is the B61-13, whose first manufacturing unit the Nationwide Nuclear Safety Administration heralded this week as a part of the great modernization of the U.S. nuclear stockpile. As stewards of the stockpile, my colleagues and I are liable for making certain the unerring reliability of those programs, in addition to reconfiguring them when needed to fulfill evolving threats. Though nuclear deterrence has proven exceptional consistency by the a long time — the triad of land-, sea-, and air-based weapons is kind of the identical as we speak because it was in 1960 — nuclear weapons are periodically tailor-made in response to fluctuations within the safety atmosphere. Simply as adversaries modify how they defend the belongings they worth most, the US calibrates its instruments to carry them perpetually in danger. The B61-13 is the newest manifestation of this precept. Designed to offer enhanced capabilities in opposition to sure more durable and large-area navy targets, or in Pentagon parlance to “deny an adversary sanctuary from assault,” the B61-13 is a steppingstone towards a extra definitive resolution to a longstanding navy problem.
Defeating hardened targets is a perennial aspiration in fashionable warfare. Throughout World Battle II, the German Kriegsmarine constructed a naval base at Lorient, on the Atlantic coast of France, that was all however impervious to Allied bombing. Constructed with 3.4 million cubic ft of concrete — in comparison with the Hoover Dam’s 4.4 million — and that includes a seven-layer, 25-foot bolstered roof, the bottom’s submarine pens enabled the predations of German U-boats throughout the Atlantic. In a whole bunch of sorties, Allied bombers pummeled the fortress mercilessly from the air, together with with 12,000-pound “Tallboy” ballistic bombs, to no avail. In exasperation, the Allies lastly shifted to pulverizing the encompassing metropolis to kill important personnel and lower provide traces to the bottom, which remained insuperable till the very finish of the conflict.
Within the following a long time, militaries the world over constructed command facilities and different services that weren’t solely closely bolstered however buried deep beneath the Earth, presenting a vexing downside to targeteers. Naturally, strategists seemed to nuclear weapons as a possible resolution. If a system may very well be designed to penetrate soil, rock, and concrete earlier than detonating, the consequences would drastically enhance the efficacy of the weapon in opposition to probably the most forbidding constructions. As early as 1952, the Mark 8 nuclear bomb was launched to the U.S. stockpile with the means to succeed in and destroy such targets.
But, as weapons capabilities superior, so did feats of structural engineering to defend in opposition to them. The Moscow Metro, famously deep by the requirements of the world’s subways, was designed partly to double as a large bomb shelter for the Kremlin management, motivating ever extra highly effective weapons within the U.S. stockpile to compromise it. Immediately, the problem is much more daunting. Weapons designers are responding to dictates from the very best ranges of the U.S. authorities to take away the likelihood that enemy belongings could be positioned past the attain of America’s nuclear pressure.
The final two Nuclear Posture Critiques — periodic presidential directives on the function of nuclear weapons in U.S. nationwide safety — have emphasised the defeat of particularly cussed targets. President Donald Trump’s first Nuclear Posture Evaluate, issued in 2018, cited North Korea’s reliance on hardened and deeply buried services to safe the Kim regime, pledging to “area a spread of standard and nuclear capabilities in a position to maintain such targets in danger.” President Joe Biden’s, launched in 2022, echoed the theme, vowing to “leverage current capabilities to carry in danger arduous and deeply buried targets” and “develop a permanent functionality for improved defeat of such targets.” Congress, too, has joined the refrain. The Fiscal Yr 2023 Nationwide Protection Authorization Act directed a research on choices to destroy arduous and deeply buried targets, together with a “proposed technique for fielding such capabilities in enough portions and making different changes to the technique and plans of the US to account for the rising arduous and deeply buried goal set…”
The B61-13 represents an intermediate reply to those edicts as much more efficient devices are being evaluated. Whereas the bomb will present new navy capabilities, it won’t be a novel weapon within the sense of being assembled from wholly new elements and supplies. Quite, the system is a modification, a subset of weapon modernizations that improve current warheads with new operational traits. Many of the weapons within the U.S. nuclear arsenal had been constructed within the Nineteen Seventies and Nineteen Eighties, and the B61 is certainly one of seven programs present process modernization to increase their operability or add additional capabilities. The deliberate W93 warhead, against this, will probably be an altogether new, fashionable weapon.
As with every complicated electro-mechanical system, elements and supplies in nuclear warheads degrade over time. To make sure their continued security and reliability, engineers scrupulously analyze each element — greater than 6,000 particular person components within the case of the B61 — and decide whether or not to reuse, restore, or substitute them. The modernization course of resolves getting older and efficiency points, enhances security options, improves the safety of the weapons, and might, as within the case of the B61-13, impart new navy attributes.
Among the many most exceptional facets of the B61-13 program is the velocity with which it’s being completed with out disruption to the broader modernization marketing campaign. The primary usable bomb was accomplished virtually a yr earlier than the unique goal date and fewer than two years after this system was introduced. For a nuclear enterprise typically seen as working at a languid tempo over the past 20 years, this was the most recent achievement that signaled a newfound aggressiveness by the Nationwide Nuclear Safety Administration. In 2023, the company delivered greater than 200 modernized weapons to the Navy and Air Drive, probably the most in a single yr because the finish of the Chilly Battle. Conscious of the deteriorating safety atmosphere, program managers made various daring selections, typically consciously accepting calculated dangers, to speed up the manufacture of the B61-13.
To be truthful, compression of the timeline was enabled partly by the sooner B61-12 life extension program, which accomplished its closing unit in late 2024. By profiting from manufacturing gear and processes from the sooner program and utilizing frequent elements, the B61-13 progressed way more shortly than deliberate. This system largely sidestepped the steep studying curve that attends a brand new modification. Usually, technical groups should be constructed and educated to carry out growth, engineering, testing, and manufacturing, however by harnessing the identical engineering cadre and strategies from the earlier program, the design timeline was drastically lowered. But, these elements don’t paint the complete image. The result hinged to a big diploma on changes to the chance tolerance of the scientists and engineers managing this system, who’re, by nature and coaching, a technically conservative bunch.
Though they maintained their customary vigilance in opposition to security and safety dangers, the engineers had been extra forgiving of programmatic danger within the curiosity of transferring swiftly. By streamlining, and in some instances combining, “design gates” — the exacting opinions carried out at every stage of a weapon design course of — the engineers considerably shortened the timeline to start manufacturing. These economies resulted in B61-13 {hardware} “check builds” starting merely three months after this system obtained authorization and appropriation from Congress. Additional efficiencies had been then devised for the manufacturing course of itself.
In a typical modernization program, earlier than the primary unit of a brand new weapon is ever produced, it should cross an exhaustive collection of qualification assessments to make sure the system will operate reliably in each atmosphere. These assessments contain a mixture of pc modeling and simulation in addition to bodily assessments of weapon elements. The marquee step within the course of is to conduct “flight assessments” wherein high-fidelity replicas of the bomb — with all the interior gadgetry however not one of the fissile materials — are dropped from the plane that delivers the actual factor. For the B61-13, these qualification assessments are occurring in parallel with the manufacturing of stay models. To the uninitiated, it’s inconceivable to understand the unorthodoxy of this method, or the willpower required for the engineers to calm down their traditional meticulousness. Reassured by a long time of B61 design and qualification knowledge, program managers developed a phased plan for simultaneous qualification and manufacture that allowed the usual schedule to be lower in half. Whereas there was some danger concerned, the sooner program impressed confidence that it was minimal, and properly definitely worth the accelerated supply.
Vindication of those practices could enable them to be transposed to future modernization efforts, with implications for his or her manufacturing timelines. So, too, may different facets of the B61-13 program. Specifically, the method featured a unprecedented stage of cohesiveness between the laboratories that designed the weapon and the crops liable for its manufacturing. In earlier eras, relations between parts of the nuclear complicated had been typically marked by institutional rivalries and cultural idiosyncrasies that subtracted from effectivity. The B61-13 may be very a lot a group effort. The Los Alamos and Sandia Nationwide Laboratories in New Mexico handle the physics and programs engineering, whereas manufacturing is carried out on the Pantex Plant in Texas, Kansas Metropolis Nationwide Safety Campus in Missouri, Y-12 Nationwide Safety Complicated in Tennessee, and Savannah River Web site in South Carolina. Specialists from every web site collaborated carefully from the start, consciously avoiding the stove-piping that has characterised weapons packages in prior a long time.
When full, along with having its service life prolonged, the B61-13 will boast a higher accuracy than its forebearers by advantage of a contemporary “tail package meeting” — the fins that information and stabilize the weapon throughout its descent. The bomb’s yield will probably be greater than its older sibling, the B61-12, contributing to its utility in opposition to sure more durable and large-area targets. Owing partly to those benefits, the variety of B61-12s constructed was lowered by the identical variety of B61-13s that will probably be produced. Consequently, the brand new modification won’t enhance the general variety of weapons within the U.S. stockpile.
In fact, sooner or later, America’s leaders could deem it needed to construct extra nuclear weapons to fulfill navy necessities. Russia, China, and North Korea are aggressively increasing and modernizing their nuclear capabilities with lavishly funded building tasks and weapons packages. As the US confronts the problem of deterring a number of nuclear-armed states concurrently, its leaders will repeatedly appraise the suitability of the U.S. nuclear posture to this activity. However what’s abundantly clear, even with out an uptick within the measurement of the stockpile, is that qualitatively new capabilities will probably be needed to carry adversary targets in danger.
America’s nuclear modernization program is already set to ship a pressure with drastically enhanced range of weapon traits and supply autos. The deliberate nuclear-armed sea-launched cruise missile, for example, will present the Navy with appreciable new optionality to discourage China within the Indo-Pacific. Work is properly underway on the Air Drive’s Lengthy-Vary Standoff cruise missile. Ought to extra nuclear capabilities be wanted to beat built-in air and missile defenses or present extra proportional theater response choices, warhead design and manufacturing can now be carried out on a timeline unimaginable a decade in the past.
Even then, there was cause for optimism that nuclear weapons would proceed to recede in relevance, as that they had within the decade prior. But the conduct of America’s adversaries within the intervening years has made clear that nuclear deterrence will stay a dominant characteristic of the worldwide panorama for the foreseeable future. Deterrence will not be magically achieved by reaching an arbitrary threshold of missiles and bombs — it’s a situation painstakingly attained and preserved by fielding the proper variety of the proper weapons in the proper locations. The B61-13 is merely the most recent output of the formulation used to form America’s nuclear arsenal, whose knowledge will finally be affirmed if these weapons by no means have for use.
David A. Hoagland serves because the Nationwide Nuclear Safety Administration’s appearing deputy administrator for protection packages, with accountability for sustaining the protection, safety, and reliability of the U.S. nuclear weapons stockpile. Previous to his present function, he served in different parts of the Nationwide Nuclear Safety Administration and on the Nationwide Safety Council employees, the place he targeted on countering nuclear terrorism and nuclear proliferation.
Picture: Sandia Nationwide Laboratories
