Stephen Schwartz is guest-blogging at DefenseTech. I am cross posting his piece on the Reliable Replacement Warhead.
Remember those commercials for Lay’s potato chips where the announcer says that Lay’s are so good that you can’t eat just one? Well, with a slight modification that slogan now applies equally well to the nuclear bureaucrats at the DOD, the Department of Energy’s National Nuclear Security Administration, weapons designers at the Los Alamos and Lawrence Livermore national laboratories, and their patrons in Congress.
Kudos to Hans Kristensen of the Federation of American Scientists for discovering that the ambitious Reliable Replacement Warhead program (see my previous post on that subject here) isn’t just about developing one new, more robust, standardized design to eventually replace every weapon in the U.S. nuclear arsenal, which was its original purpose when proposed by Congress in late 2004. According to a chart on the web site of the Deputy Assistant to the Secretary of Defense for Nuclear Matters, DOD’s long-term vision is that in about 14 years there will be as many as four RRWs in the arsenal, along with up to four types of “refurbished, legacy warheads” from the existing stockpile. There are presently nine operational warhead types in the arsenal.
Teams from Los Alamos and Livermore each submitted their proposed designs for a replacement for the 100 kiloton W76 warhead (some 1,600 of which are currently deployed on Trident II D-5 submarine-launched ballistic missiles) to the NNSA earlier this year. One proposal alone reportedly ran to more than one thousand pages. As early as November, the NNSA will select the winning design, sending the program into its next phase.
Even before today’s revelation, however, others were working to expand the scope of the RRW. In a revealing interview with the San Francisco Chronicle last January, NNSA administrator Linton Brooks indicated that new weapons—most likely with new or enhanced capabilities—would be the probable outcome of the RRW program. “I don’t want to mislead you,” said Brooks. “I will personally be very surprised if we can get the advantages we want without redesigning the physics package [the explosive components of the warhead].”
In late June, Senator Pete Domenici (R-NM), chairman of the Senate appropriations subcommittee with responsibility for nuclear weapons funding, added $35 million to the administration’s $27 million request for the RRW to accelerate the program, including $10 million for the specific purpose of initiating a second warhead design competition.
It remains to be see whether this extra funding survives a House-Senate conference on the fiscal 2007 spending bill. But it is noteworthy that longtime critic of the NNSA, supporter of the RRW, and Domenici’s House counterpart, Rep. David Hobson (R-OH), bluntly warned administration officials last March against using the RRW to develop new nuclear weapons. Said Hobson, “This is not an opportunity to run off and develop a whole bunch of new capabilities and and new weapons…. We’re not going out and expanding a whole new world of nuclear weapons as we get in[to] this Reliable Replacement Warhead situation.”
—Stephen I. Schwartz
This is going from bad to worse. Brooks is clearly indicating that they are back to using plutonium pits. Bob Peurifoy wanted to use Uranium because it was cheap to manufacture with and didn’t have the aging uncertainties. A major problem is that the Uranium weapons will have a larger fission yield component as I commented on in Jeffrey’s previous RRW post.
So, why are we doing this at all? To get bigger, heavier, dirtier, untested and still expensive weapons? It makes no sense when the current weapons work fine.
I think they are trying to field a new technology, and here is what I think it is:
The most obvious mission requirement looking forward for US nukes is selectable yield, lowest attainable fallout.
To do this, the objective is to get the highest possible primary specific energy density as possible. As I mentioned before here, up in the range of 40 tons TNT per pound primary weight. There is a limit to how light you can make the primary if it’s all wrapped in HE and tamper and needs to compress the pit to 1.5x+ solid density. 200-300 pounds or so, it seems for the fancy warheads.
I think that to beat this, and what the weaponeers want to build in the RRW, is that the primary explosives are on the outside of the radiation case, and use the case itself as the forming tamper for the pit. Then, we are left with a bare pit hanging in space inside the radiation case. You use more Pu because the compression isn’t so high, but the payback is that you don’t have to heat up the implosion mechanism too. Overall, the bomb is heavier, but the fission ratio is much lower. In some respects, the hydrodynamics are simpler.
Problem is that as much as they say they won’t test this, it seems to me that they’d have to test it. Only way around that would be if they had already tested it, e.g. in enhanced radiation warhead designs in the 80’s.