What happened
On December 10, 2018, an Indigo Airbus A320, registration VT-ITR, was descending through flight level 170 toward Kolkata Airport (CCU) in India. During the descent, the flight crew received an ECAM warning indicating 'Lavatory Smoke'. In response to the warning, the crew declared an emergency and subsequently completed a successful landing.
Following the landing, a ground inspection was performed on the aircraft. The inspection revealed that the No. 2 (right) engine was low by approximately 13 quarts of oil. A ground run of the engine confirmed that this oil deficiency was the source of the smoke and odor detected in the cabin.