Sisters Aoki Hagane no Arpeggio: Ars Nova : Season 1 Episode 11

Restored and strengthened by Takao's sacrifice, 401 forges on to America with 400 and 402 in pursuit. The sister ships face off in the waters of Hawaii. With enhanced specs, five Mental Models, and Gunzou's tactical prowess, the twin submarines are no match for the new 401... but Iona wishes them no harm.