The "B" (actually "Б") in her designation stands for большая (bolshaya, "large")—Foxtrots were the Soviet Navy's largest non-nuclear submarines.

[citation needed] In 1989, in the Sea of Japan while charging batteries on the surface, B-39 came within 500 yards (460 m; 0.25 nmi) of an Oliver Hazard Perry-class frigate of the US Navy.

With the shroud cut away, tourists could look through the partially raised periscope (which is directed toward the USS Midway museum, some 500 yards (460 m; 1,500 ft) away).

In 2010, B-39 was proposed to be sunk to create an offshore diving reef,[4] but an outcry from teachers and enthusiasts ensured the sub would stay on display a while longer.

[citation needed] During the 2010s, B-39 had become badly rusted with large holes visible in the outer hull and upper deck.