Mysterious sonic boom in Bengaluru: Here’s what happened

A mysterious sonic boom at rattled the citizens as well as the authorities in Bengaluru’s aerospace hub at around 1:30 pm. Rumours of an earthquake, an explosion or a fighter jet cruising at top speed started surfacing on social media, with people sharing videos and photos from the incident. However, it has been learnt that the boom was caused due to IAF’s fighter jet test flight.

"It was a routine IAF test flight involving a supersonic profile, which took off from Bengaluru airport and flew in the allotted airspace outside the city limits," a defense official stated in a tweet much later after the incident occurred.

The fighter aircraft was of the IAF's Aircraft Systems and Testing Establishment (ASTE), which uses the defence airport of the state-run Hindustan Aeronautics Ltd (HAL) in the city's eastern suburb for test flights.

The ASTE's test pilots and flight test engineers test out all military aircraft. The sonic boom was heard while the aircraft was decelerating from super-sonic to sub-sonic speed between 36,000 and 40,000 feet altitude. Karnataka State Natural Disaster Management Committee official said seismo meters did not capture any ground vibration, which occurs during a mild tremor. 

A city fire brigade official told IANS the massive sound could be due to mining blast of rocks in a quarry for construction.