On 4 December 1971, Wing Commander A.A. D'Costa, the commanding officer of a fighter bomber squadron, was the first to strike at the enemy's Risalwala airfield. Next day he led a mission to Christian Mandi and destroyed three tanks. The following day he led an attack on a concentration of tanks at Dera Baba Nanak, notwithstanding intense anti-aircraft fire. On 7 December, he carried out a low-level photographic reconnaissance mission in the Sulaimanki area. He followed this up by leading an attack on the same day on the railway station at Narowal where he personally destroyed and damaged many railway wagons and some installations. Thereafter he flew a number of reconnaissance missions, bringing back a large volume of intelligence and other missions against railway marshalling yards and Raiwind and the Kasur-Lahore railway track, destroying a large number of wagons and causing devastation at each target in the face of intense anti-aircraft fire, and against Pakistani air opposition.

Throughout the operations, Wing Commander D'Costa displayed conspicuous gallantry, determination, leadership and professional skill.