Russia’s second Severodvinsk-class submarine K-561 Kazan , which is a modified Project 08851 Yasen-M design, went to sea for the first time for builder’s trials on September 24.

The massive nuclear-powered guided missile submarine (SSGN) was designed by the Malachite design bureau in St. Petersburg and was built in the northern Russian city of Severodvinsk. Kazan was launched on April 8, 2027, and was originally expected to be delivered to the Russian Navy this December, but construction work on the vessel was delayed. At present, Kazan is not expected to be delivered to the Russian Northern Fleet until at least 2019. Nonetheless, the Russian vessel is expected to be the most formidable enemy submarine the United States Navy has ever faced.

The United States Navy was already impressed with the original Severodvinsk, which is an older design that had been under construction since 1993 before eventually being commissioned into service in December 2013. Shortly thereafter in 2014, Rear Adm. Dave Johnson, who was then Naval Sea Systems Command’s (NAVSEA) program executive officer (PEO), told me he was so impressed with the Russian submarine that he had a model of Severodvinsk built for display outside of his office.

“We’ll be facing tough potential opponents. One only has to look at the Severodvinsk, Russia’s version of a [nuclear guided missile submarine] (SSGN). I am so impressed with this ship that I had Carderock build a model from unclassified data.” Johnson said during the Naval Submarine League’s 2014 symposium in Falls Church, Va . “The rest of the world’s undersea capability never stands still.”

Later in 2016, Rear Adm. Michael Jabaley, who was then the Navy’s program executive officer for submarines—speaking at the Center for Strategic and International Studies— said on July 8, 2016, that the Navy launched its Acoustic Superiority Program to improve the performance of Virginia-class attack submarine as a response to the advent of the Severodvinsk-class.

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