Any crew members who survived the initial accident are likely to have waited in the cold and dark for help, as the damaged submarine filled with water. Given the extent of the damage to the front and side of the Kursk, it was thought any survivors would probably have been towards the rear of the vessel, where one of the rescue hatches is located. In such situations submariners are trained to minimise movement and slow breathing in order to conserve oxygen and slow down the build-up of carbon dioxide. Military experts say morale and strong leadership are also crucial factors for survival. Submariners are among the most highly trained of seamen, but in the case of the Kursk crew their ship lived up to the macabre sailors’ nickname for submarines, becoming an iron coffin.

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