Last week the National Nuclear Security Administration (NNSA) released its Fiscal Year 2017 Stockpile Stewardship and Management Plan, the agency’s annual update on its 25-year plan for the U.S. nuclear weapons stockpile. It is the most comprehensive, long-term plan related to nuclear weapons available from any government.
The key takeaway from this year’s stockpile plan is that very little has changed since last year. The overall vision has not changed, the schedule has not shifted, and the budget estimates, while modestly smaller for some projects, are still harrowingly large.
And that is a bad thing, because the NNSA’s plan has significant problems.
First among these, by a wide margin, is the plan’s over-reach. In particular, the NNSA’s “3+2” plan to replace the entire U.S. nuclear stockpile with a suite of newly designed nuclear warheads is far more aggressive that what is required. (See my colleague’s detailed report for an in-depth examination of why.)
The “2” in 3+2 refers to the two air-based weapons: the B61-12 bomb and the W80 warhead for the proposed new air-launched cruise missile. These are the first two weapons in the 3+2 plan queue, and the approach for their development and production are relatively modest (more on that later).
The “3” refers to three new “interoperable” warheads for delivery by land-based and submarine-based ballistic missiles. These would have a “common nuclear explosive package and common or adaptable non-nuclear components.” The “nuclear explosive package” (NEP) is the core of a nuclear weapon, composed of a primary and a secondary. The fission of plutonium in the primary ignites a fusion reaction in the secondary, together creating the enormously large yield of today’s nuclear weapons.
The NEP designs for all deployed weapons have been explosively tested, but under the 3+2 plan, this would change.
New Untested Warhead Designs
For the first time since the United States stopped explosive testing of nuclear weapons in 1992, the NNSA is proposing to deploy new warhead designs that would incorporate fundamental changes to the nuclear explosive package. They plan to take the primary from one warhead (the W87), and the secondary from another weapon (as yet unidentified publicly) and combine them in a new nuclear explosive package. This new NEP would not be explosively tested; instead, its performance would be validated by computer models.
Why would the NNSA do this? Because the W87 warhead deployed on U.S. land-based missiles, while widely recognized as the safest and most advanced design in the stockpile, is too large to fit on the Trident missiles carried by U.S. submarines. The U.S. Navy is not going to redesign its missiles, so the NNSA proposes to design new, smaller warheads that will fit.
In fact, the NNSA proposes three interoperable warheads that will replace all four current missile-carried warheads: the W76 and W88 on submarines and the W78 and W87 on land-based missiles. The first interoperable warhead (IW-1) is intended to replace the W78 and some portion of the W88s. Development work on the IW-1 started back in 2012, then was stopped in 2014 and is now scheduled to begin again in 2020. Production is slated to start in 2031 and run through 2043.
The schedule delay happened when the Navy revealed that it was not at all excited about the proposed interoperable warhead, while the Air Force decided to prioritize the proposed new air-launched cruise missile, which will require a life extension program for its warhead.
The first problem with the interoperable warhead proposal is the ‘mix-and-match’ approach, marrying two major nuclear components that have never been tested together. This could reduce technical confidence in the resulting weapons. JASON, an independent advisory group of scientists that has long advised the government on defense and technical issues, warned that the “. . . greatest care in the form of self-discipline will be required to avoid system modifications, even if aimed at ‘improvements,’ which may compromise reliability”.
As a result, the ‘mix-and-match’ approach could lead some to insist that the United States must “proof test” the new designs with underground nuclear explosive testing, breaking a decades-long moratorium. This would encourage other countries to resume testing, setting off a dangerous new arms race.
But even beyond the fundamental technical challenge of fielding three new, untested warhead designs, the 3+2 plan creates additional—and unnecessary—problems. First is the fact that the three “common nuclear explosive packages and common or adaptable non-nuclear components” will actually have to be six different designs, because each warhead will have to fit in the different re-entry vehicles for the submarine-based and land-based missiles. Rather than the four missile warhead types as there are now in the stockpile, there will be six designs: three interoperable warheads, each with two distinct variants.
Second—and more problematic—pursuing this approach will require the NNSA to produce in bulk new plutonium “pits,” the fissile core of the primary. The plan is to use W87 or W87-like pits in the IW-1. After New START is fully implemented in 2018, it is reasonable to assume the United States will deploy some 200 W78 warheads and keep some 200 in the hedge, and deploy roughly 400 W88 warheads (with none in the hedge). Replacing all the W78s and half the W88s will thus require some 600 IWs—and hence roughly 600 W87 pits. The United States has over 500 W87s, and after 2018, will likely deploy some 200 and have 200 in the hedge. Thus, there will be 100 W87 pits available for the IW-1. In addition, it is possible the United States would likely dismantle the 200 W87 warheads in the hedge to use the pits for the IW-1. So to meet the need for 600 W87 pits, the United States will have to manufacture 300-500 new ones before 2043.
And that will put yet another significant strain on the NNSA, which stopped producing pits in bulk in 1989, when the FBI shut down the Rocky Flats production facility for violating federal environmental laws. More recently the NNSA created a boutique production capability at Los Alamos National Lab in New Mexico, but even that was shut down for more than two years because of safety problems and is only now resuming production of around 10 pits per year. The NNSA plans to expand this capability to 30 a year by 2030, and to 50-80 a year by 2050. Just the first step of creating a slightly larger-scale capacity to make the extra W87 pits for the IW-1 warhead will require a decade of work and a massive investment.
If the NNSA simply refurbished existing warheads rather than designing and producing the new IWs, it would not need to produce new pits. In 2006, the NNSA concluded that the existing pits in the U.S. nuclear stockpile were reliable for at least 85 years. This means that, for many years to come, the only requirement for new pits will be if the NNSA decides to field new weapons like the IW-1; there is no need to produce them now to maintain the existing stockpile.
A third problem is that the 3+2 plan would replace some portion of the deployed W88 warheads with IW-1 warheads—even though the W88s won’t need to be replaced. The W88 requires some refurbishment that has to be finished well before the IW-1 will be completed, and is now entering a more modest project (known as an Alteration, or Alt) to update a few elements and replace limited life components. The Navy successfully argued that the project should include replacing the conventional high explosives in the warhead, which a government official told me could give it a new lifespan of as long as 30 years. The new W88 warhead will be in production from 2020 to 2025. So, assuming a 30-year lifespan, they would need to be replaced by 2055. For the IW-1, the FY2017 stockpile plan notes that “initial production will go to the Air Force” (to replace W78s). But by the end of production in 2043, the NNSA would be replacing W88s that should be good for as long as 12 more years.
A Better Approach
If the NNSA abandoned the 3+2 plan and simply took a straightforward life extension approach to maintaining the stockpile, it would avoid all of these problems. The model for this approach is the W76 life extension program, which is updating the warhead that is the bedrock of the U.S. nuclear deterrent. The W76 project, which will wrap up in 2020, is producing some 1,600 refurbished warheads, with relatively modest changes overall (and none to the nuclear explosive package), at a cost, according to the FY 2017 stockpile plan, of roughly $4 billion in FY2016 dollars.
That brings us back to the relatively modest plans for the first two weapons in the 3+2 plan. Those are the new version of the B61 gravity bomb and the update to the W80 warhead in the planned new nuclear-armed cruise missile.
The B61 life extension plan is relatively modest only in comparison to the approach for the interoperable warheads. While the NNSA is not making changes to the nuclear explosive package in the B61, it is undertaking a very far-reaching update to what will become the only gravity bomb in the U.S. stockpile. As one government official put it to me, after developing a range of options for the B61 life extension program, the NNSA ended up deciding between a Cadillac and a Maserati. (In the end, the NNSA picked the Cadillac only because it was told the Maserati was not feasible due to its inclusion of undeveloped technologies.)
With that high end approach, the cost of the B61 life extension program is dramatically more expensive than for the W76 program, while producing far fewer weapons. Less than 500 of the new gravity bombs will cost between $7 billion and $9 billion in FY 2016 dollars, roughly twice the early estimates for the project. On a per warhead basis, the W76 will cost around $2.5 million each, while the B61 will cost $20 million each (not including additional Pentagon costs).
The cost for the life extension program for the W80 warhead, to be used in the proposed new cruise missile, is unfortunately closer to the scale of the B61 than that of the W76. According to the FY2017 stockpile plan, it will cost between $6 billion and $8 billion (again in FY2016 dollars) to produce what outside experts estimate is roughly 500 updated warheads. While the NNSA has not finalized the scale of work for the W80 program, it is disappointing to see the costs are estimated to be significantly more than those for the W76.
Doing What is Required, Not What Might be Desired
The NNSA has a long, long history of developing far-reaching projects that end up costing far more than initially anticipated and taking far longer than planned. Many of those projects ended up being significantly scaled back; many others were cancelled outright. The technically aggressive, resource-intense 3+2 approach outlined in the FY2017 Stockpile Stewardship and Management Plan similarly over-reaches.
To match its capabilities and resources to what is required to maintain the stockpile, the NNSA needs to cut back the scale of its plans so that the work that has to be done can be done. In just one example, the investments needed to produce new plutonium pits for the IW program will compete with the billions of dollars and significant human resources the NNSA has to invest to update its capability to manufacture highly enriched uranium (HEU) components at the Y-12 plant in Tennessee.
Until a more manageable approach is developed throughout the NNSA’s programs, the agency risks wasting tens of billions of dollars and countless staff resources on projects that are doomed to failure, while creating unnecessary technical risk. A change is needed to an approach that devotes the needed resources to meet the required goals, with a reasonable margin of error, but nothing more.