In May 1964, the Government of India decided to appoint Singh as the Chief of the Air Staff (CAS), succeeding Air Marshal Aspy Engineer, DFC. On 1 August 1964, Singh was promoted to the rank of Air Marshal and took over as the 6th Chief of the Air Staff. When appointed as Chief of the Air Staff of the Indian Air Force, he was around 45 years old. Indo-Pakistani War of 1965 In August 1965, as part of Operation Gibraltar, Pakistan attempted to infiltrate forces into Jammu and Kashmir to precipitate an insurgency against Indian rule. This was followed by a full-scale war between India and Pakistan in the Western theatre. In September, Pakistan launched Operation Grand Slam in which an armoured thrust targeted the Akhnoor and Chhamb regions in Jammu. The Indian Air Force responded to an urgent call for air strikes against the Pakistani Army. Singh was summoned into the Defence Minister Y B Chavan's office with a request for air support. With a characteristic nonchalance, he replied "in an hour." True to his word, the armoured thrust was hit in an hour by the IAF. Although the IAF suffered some losses early on, it bounced back and scored strategic victories during the conflict . The war ended with a ceasefire being declared by both nations on 23 September. Singh led the IAF during the war showing unparalleled leadership and remained cool and inspirational throughout. Singh was awarded India's second-highest civilian award, the Padma Vibhushan for his leadership during the war. On 15 January 1966, in recognition of the contribution of the IAF, the post of the CAS was upgraded to the rank of Air Chief Marshal. Singh became the first Officer to hold the rank of Air Chief Marshal. On 7 June 1966, with the retirement of General Jayanto Nath Chaudhuri, Singh took over as the Chairman of the Chiefs of Staff Committee, a post he held until he retired. In 1967, in a rare honour to a non-British Service Chief, Singh was invited to receive the salute as the reviewing officer of the passing out parade at his alma mater, the RAF College Cranwell. After heading the IAF for almost five years, the second-longest term as Chief of the Air Staff in history, Singh retired in July 1969, at the age of 50. Diplomatic and Political career In 1971, after his retirement, Singh was appointed India's