The Hunt for Red October vessel. It is equipped with a cutting-edge silent propulsion system, known as the caterpillar drive, that makes audio detection by passive sonar extremely difficult and enables the submarine to sneak its way into American offshore waters and launch nuclear missiles with little or no warning. As the ship leaves the shipyard at Polyarny, Ramius kills Ivan Putin, his political officer, to ensure that he will not interfere with the defection. Initially, Ramius was instructed to conduct military exercises with Soviet attack submarine "V. K. Konovalov", commanded by his former student Viktor Tupolev, for the purpose of testing the effectiveness of
The Hunt for Red October are many deviations, including "Red October" traveling up the Penobscot River in Maine to dry dock, and the "caterpillar drive" being described as a magnetohydrodynamic drive system, essentially, "a jet engine for the water". The film received mainly positive reviews from critics, holding an 87% rating from Rotten Tomatoes based on 66 reviews. It was the 6th top-grossing film of the year, generating $122 million in North America and more than $200 million worldwide in box office. In a 1991 interview, Clancy remarked of the film's success: "It was reasonably true to the spirit of the book, although the movie