He then set out to become the first man to swim the oceans of the five continents in one calendar year (1966). Initially, he needed to raise Rs 45,000 to pay the Indian navy to accompany him to record and navigate the Palk Strait swim. Sen managed to raise half the money through sponsors (notably the Kolkata daily, "The Statesman") and the balance was provided by then Prime Minister Indira Gandhi. She further extended full support of the Indian Navy (The INS Sukanya and the INS Sharada) to accompany him for the Palk Strait swim.