WASHINGTON, D.C. -- The Department of Energy’s National Nuclear Security Administration (NNSA) announced today that the first W88 nuclear warhead to employ a replacement pit officially was certified for entry into the United States nuclear weapons stockpile.

An essential piece of every U.S. nuclear weapon, the pit is typically made of plutonium and acts as a trigger, allowing a weapon to function. NNSA recently restored its ability to manufacture pits in small quantities.

“Rebuilding this W88 was an enormous undertaking that took NNSA over a decade and required the tremendous scientific and engineering expertise of the entire nuclear weapons complex,” said NNSA Administrator Thomas D’Agostino. “I am proud that we were able to get the job done and accomplish this great feat with the W88.”

Under NNSA’s Stockpile Stewardship Program to ensure the reliability, safety and security of the nuclear weapons without underground nuclear testing, weapons are regularly taken apart and examined. Most of the weapons are reassembled and returned to the stockpile; however, some of the inspections are so thorough that the pit and other components are destroyed and need to be replaced.

The W88 warhead was able to be re-assembled, certified and accepted into the stockpile with a replacement pit without conducting an underground nuclear test. Certification was possible because of NNSA’s powerful experimental tools, supercomputers, and improved computer models.

The restored W88 warhead, assembled at NNSA’s Pantex Plant, is the first nuclear weapon to use a replacement plutonium pit. In July, NNSA’s Los Alamos National Laboratory produced the first pit for the stockpile in 18 years. The warhead also required a replacement gas transfer system that was manufactured at NNSA’s Kansas City Plant and filled with gas at the Savannah River Site. The gas transfer system is essential to assure a weapon’s performance.

“Any replacement component added to a system as complex as a nuclear weapon presents a tremendous challenge. As we extend the lives of our current aging warheads, and continue to move further and further from the original tested designs, this process becomes increasingly complicated,” said D’Agostino.

Because of the difficulty of managing an aging stockpile, NNSA is in the early phases of exploring alternative means to ensure the safety, security and reliability of its weapons. Through a program called the Reliable Replacement Warhead (RRW), NNSA is investigating a lower risk approach to assure long-term confidence in the reliability of the nuclear stockpile. RRW will use parts, materials and manufacturing procedures that will make assembly and disassembly easier, safer and more secure and could eventually replace the difficult, expensive, and increasingly risky life extension process.

Established by Congress in 2000, NNSA is a separately organized agency within the U.S. Department of Energy responsible for enhancing national security through the military application of nuclear science. NNSA maintains and enhances the safety, security, reliability and performance of the U.S. nuclear weapons stockpile without nuclear testing; works to reduce global danger from weapons of mass destruction; provides the U.S. Navy with safe and effective nuclear propulsion; and responds to nuclear and radiological emergencies in the United States and abroad.

Media contact(s):
NNSA Public Affairs (202) 586-7371