 Complete the following phrase:  The Eastern Air Command is one of the five operational commands of the Indian Air Force. Currently headquartered in Shillong in Meghalaya. Named No. 1 Operational Group at the time of its inception, 27 May 1958, it was based at Ranikutir in Kolkata as a part of the Govts increasing emphasis on defence of the eastern borders. The Operational Group was upgraded as Command on 1 December 1959 with headquarters at Fort William, Kolkata and Air Vice Marshal KL Sondhi as the first AOC-in-C of the Eastern Command Indian Air ForceRank structure. After the 