Pinto was commissioned in August 1940 as a Pilot Officer. He served with the No. 12 Squadron RAF for about two years. He was among the 24 pilots who participated in the Battle of Britain. In 1942, he returned to India and joined the oldest squadron of the IAF, No. 1 Squadron IAF, then commanded by Squadron Leader Henry Runganadhan. After a short stint, he was transferred to No. 7 Squadron IAF. In October 1943, he was promoted to the acting rank of Flight Lieutenant and took command of a flight. The commander of the other flight in the squadron was Flt Lt Pratap Chandra Lal. The squadron was equipped with the Vultee A-31 Vengeance dive bombers and supported the Chindits. The squadron also helped in relieving the Siege of Imphal.