The National Nuclear Security Administration and Air Force Global Strike Command earlier this month conducted two joint flight tests of mock B61-7 and B61-11 nuclear gravity bombs.
Two B-2A Spirit stealth bombers dropped the joint test assemblies over the Tonopah Test Range in Nevada in the successful test, the NNSA said in a press release. Joint test assemblies are simulated weapons with no nuclear materials or yield capability that are equipped with sensors and a flight recorder.
“The primary objective of flight testing is to obtain reliability, accuracy, and performance data under operationally representative conditions,” the release says. “Such testing is part of the qualification process of current alterations and life extension programs for weapon systems. NNSA scientists and engineers use data from these tests in computer simulations developed by Sandia National Laboratories to evaluate the weapon systems’ reliability and to verify that they are functioning as designed.”
One of the bombs was an “earth penetrator” that would be used against subterranean targets, while the other was a tactical form of the B61, Defense One reported.
Rocket-Sled Test
Meanwhile, Sandia said Wednesday it is evaluating data from a safety test of the U.S. B61-12 nuclear gravity bomb.
In the March 9 trial at the NNSA laboratory in New Mexico, a B61-12 test unit was placed on a 10,000-foot rocket-sled track that launched the fake but otherwise realistic device into a steel and concrete wall. The intent was to enable Sandia engineers to study the B61-12’s safety systems to prevent unintended nuclear explosions.
The B61-12 program is intended to extend the life of the B61 gravity bomb for 20 years at an estimated cost of $8.1 billion. Most of the design work for the refurbishment of the B61 is done at the Sandia and Los Alamos national laboratories. The weapon is deployed at several bases in Europe.
The March “abnormal environment” test was the result of more than a year of preparation. It followed “normal environment” tests in 2014 and 2015 in which a rocket sled was slammed into a simulated B61-12.
“Abnormal environment tests are performed to benchmark the performance of safety features designed into weapons,” Matt Brewer, lead test engineer, said in a press release.
The fake B61-12 was loaded with an internal data recorder to collect information from the impact and “to validate computer models,” the release says. Physical tests are paired with computer modeling to evaluate the weapon in a host of accident situations.
“We will use the models to predict how our nuclear safety components will perform in numerous postulated accident scenarios without actually conducting tests,” John Sichler, head of Sandia’s Center Bomb Subassembly Production Realization Team, said in the release. “Over the past five years we’ve been improving out models. It’s remarkable how good they have become.”
Sandia spokeswoman Sue Holmes said Wednesday she did not have any information on the cost of the accident test or the timeline for completion of safety testing for the B61-12. The program just entered its final design phase, which will incorporate data from a variety of testing, she said. The first B61-12 production units are due in 2020.
