The Contained Firing Facility (CFF) at Lawrence Livermore National Laboratory (LLNL) recently marked a major milestone: its 200th explosive experiment. This milestone was achieved with a three-in-one event as shots 198, 199 and 200 were conducted simultaneously. In these hydrodynamic experiments, known as "shots," researchers observe how test materials move in the microseconds after a detonation.
"Shot Day" is a beehive of activity. Starting as early as 5 a.m., teams from the Lab's Site 300 firing operations pore over final details and conduct dry runs to test the systems.
"Everyone is at their highest level of readiness and awareness," said Anthony Regalado, who oversees Weapon Physics and Design (WPD) firing operations at both the CFF and the Outdoor Firing Facility (OFF). "What we're doing is way more than just blowing something up and getting data. It's about executing safely, securely and with intense attention to detail and quality on our nation's top security mission."
Regalado has had a bird's-eye view of the decades of experiments that led to the 200th experiment. He supported his first CFF shot as a newly hired electronics technologist in the early 2000s.
"The work we were doing inside the CFF chamber - detonating experiments containing toxic materials inside an enclosed structure - hadn't really been done before," Regalado said. "We spent years refining our processes, learning how to safely and efficiently navigate the complex and challenging modes of our operations."
"These milestone experiments often take years to develop, involving many dedicated people. At the CFF and OFF, we only see the final stage of the experiment, so we execute with a strong sense of purpose," he added.
Today, the CFF is the largest indoor firing facility in the U.S. Department of Energy complex, handling large-scale, non-nuclear experiments with full containment of hazardous materials such as beryllium, lead and depleted uranium. Because the explosion is contained, LLNL can safely collect unique data while protecting both the workers and the environment.
The Hydrodynamic Testing program at LLNL serves a wide range of customers including modernization programs, fundamental weapons science, stockpile stewardship, counterterrorism and counterproliferation efforts, and diagnostics development for national labs and partners.
At the CFF, shot data is captured using LLNL's state-of-the-art, high-speed flash X-ray machine and other advanced diagnostics. These include multiplexed Photonic Doppler Velocimetry, Broadband Laser Ranging, high-speed rotating mirror imaging, digitizers and thermocouples - a standard set for most experiments that support nuclear weapons and explosives research and development.
The ability to execute multiple shots simultaneously is a boon for customers, improving scheduling and operational efficiency. Initial diagnostic data capture for the milestone shots was excellent, and further analysis is underway. Sandia National Labs also contributed to the effort, providing diagnostics for stockpile modernization programs.
"Every shot is unique and brings its own challenges," said Kyle Sinding, the Weapon Physics and Design program group leader who oversees hydrodynamic experiments. "It's a fluid and dynamic environment, and firing operations teams truly excel in it."
Precision is critical in these experiments, Sinding explained. "You must collect the right data of the highest quality at exactly the right time. It can take years to build an experimental configuration, and once it explodes, you can't put it back together. Starting over pushes out schedules and drives up costs."
Sinding praised the dedication of the teams involved. "Our teams constantly navigate challenges while ensuring we get the data we need. They instill high confidence by taking care of even the small things at very high quality."
Regalado also highlighted the importance of thorough reviews before and after each shot. "Principal investigators and Ramrods conduct in-depth reviews of the experiment before the shot, and analyze the data captured afterward," he said. "This ensures everyone understands the bigger picture and the full context of the various programs we support, all tied to the ultimate national mission. It inspires and unifies the whole team."
For Regalado, the significance of the work goes beyond the technical aspects. "Those of us in firing operations know we're not just setting up and executing experiments - we are part of something big and meaningful," he said.
Reflecting on the milestone, Regalado expressed pride in the team's efforts. "It instills a great pride to be part of the Hydrotest Program and help achieve the Lab's national mission. It takes a large team of dedicated professionals to accomplish this. I couldn't be prouder of the team I get to work alongside every day. All the credit to our success goes to them."
-Paula Rockstroh
