 The Charlie Is had two banks of four missile tubes angled upwards on each side of the bow outside the pressure hull.The tubes were covered by large outer doors and the design was to incorporate the P-120 Malakhit (SS-N-9 Siren) medium-range anti-ship missile.Due to delays in the missile development, the missile was substituted with the shorter range P-70 Ametist (SS-N-7 Starbright) submerged launch missile which itself was a development of the P-15 Termit (SS-N-2 Styx) surface-launched missile.