On 19 December 1949 he was promoted to the acting rank of Commander. He was selected to attend the Joint Services Staff College at Latimer, Buckinghamshire. After the six-month course, he was appointed Deputy Naval Advisor to the High Commissioner of India to the United Kingdom V. K. Krishna Menon at India House, London. During this stint, he underwent a two-month attachment with the Town-class cruiser . In 1951, Krishnan returned to India was appointed Commander of the 31st Minesweeping Squadron. After a short stint, he was given command of the training ship . Lieutenant Commander S. H. Sarma was his executive officer. In 1952, to commemorate the Coronation of Elizabeth II, a massive Coronation review of the fleet was held at Portsmouth. The flagship "INS Delhi", destroyer and "INS Tir" represented India at the review. A naval armada consisting of ships from the Indian Navy, Royal Navy, Royal Australian Navy and the Royal New Zealand Navy sailed from Portsmouth to Gibraltar. The fleet carried out exercises along the way and was under the command of Lord Mountbatten. Subsequently, the Indian ships continued conducting exercises with the Mediterranean Fleet. They sailed from Gibraltar to Malta, the Greek islands and to Istanbul.