Reliable Replacement Warhead

The Reliable Replacement Warhead (RRW) was a proposed new American nuclear warhead design and bomb family that was intended to be simple, reliable and to provide a long-lasting, low-maintenance future nuclear force for the United States. Initiated by the United States Congress in 2004, it became a centerpiece of the plans of the National Nuclear Security Administration (NNSA) to remake the nuclear weapons complex.

In 2008, Congress denied funding for the program, and in 2009 the Obama administration called for work on the program to cease.

During the Cold War, the United States, in an effort to achieve and maintain an advantage in the nuclear arms race with the Soviet Union, invested large amounts of money and technical resources into nuclear weapons design, testing, and maintenance. Many of the weapons designed required high upkeep costs, justified primarily by their Cold War context and the specific and technically sophisticated applications they were created for. With the end of the Cold War, however, nuclear testing has ceased in the United States, and new warhead development has been significantly reduced. As a result, the need for high technical performance of warheads has decreased considerably, and the need for a longer-lasting and reliable stockpile has taken a high priority.

Prior nuclear weapons produced by the U.S. had historically become extremely compact, low weight, highly integrated, and low-margin designs which used exotic materials. In many cases the components were toxic and/or unstable. A number of older US designs used high explosive types which degraded over time, some of which became dangerously unstable in short lifetimes (PBX 9404 and LX-09). Some of these explosives have cracked in warheads in storage, resulting in dangerous storage and disassembly conditions.

Most experts believe that the insensitive explosives (PBX 9502, LX-17) currently in use are highly stable and may even become more stable over time.

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