On October 21, Russia tested two submarine-launched ballistic missiles (SLBM) during military exercises in the Barents Sea. According to Russia’s Ministry of Defense, the tests were intended to verify the operation of its SS-N-18 (R-29R) SLBMs, which are reportedly nearing the end of their service life. During the test, one of the missiles failed to exit the submarine’s launch canister and the submarine subsequently “returned to its home base with an unexploded missile.” The SS-N-18 is a liquid-fueled SLBM with a range of 6,500 km.