Despite increased and intensive operational activity over the past year, the Israel Navy's submarine flotilla has continued to invest heavily in officers who graduated from the submarine training course on Sunday and became official crew members. The yearlong course includes extensive physical training and basic submarine studies. The seamen are carefully selected, constantly observed and eventually split up into several teams. The first stage of the course contains exhausting sea training, including a civilian diving course. After they are divided into teams, the seamen are taught their specialization - radar operator, weapons expert, technological officer and more. Col. A., commander of Submarine Flotilla 7, told The Jerusalem Post on Sunday that despite the submarines non-stop operational duties, the navy was able to provide the trainees with fulltime instructors to accompany them throughout the course. "Our method of training is that we split them up into teams and then teach them how to work together," A. said. "They then start working in the vessel and we provide them with an instructor who follows their every step and approves them for operations at the end of the training period." The navy's three Dolphin-class submarines are the most expensive platforms in the IDF's arsenal. Germany donated the first two submarines to Israel after the first Gulf War and split the cost of the third. The submarines' diesel-electric propulsion systems requires them to surface after short periods underwater to recharge the batteries with which they operate when submerged. In 2010, the navy hopes to receive two U212 submarines it has ordered from Germany. They will be fitted with a new German technology that works with a propulsion system that combines a conventional system consisting of a diesel generator with a lead-acid battery, and an air-independent propulsion system, used for silent slow cruising, with a fuel cell equipped with oxygen and hydrogen storage. A. said the flotilla had played an active role in the Second Lebanon War, but declined to divulge what lessons were learned from its operations and how they had been implemented. He also said Sunday's graduating course was unique since it had a relatively high proportion of seamen from cities, particularly Tel Aviv. In comparison, officers at the Ground Forces Training School recently complained of a drop in the number of soldiers from large cities volunteering to become officers.