Mount Galunggung (Indonesian: Gunung Galunggung, formerly spelled Galoen-gong) is an active stratovolcano in West Java, Indonesia, around 80 km (50 mi) southeast of the West Java provincial capital, Bandung (or around 25 km (16 mi) to the east of the West Java town of Garut). Mount Galunggung is part of the Sunda Arc extending through Sumatra, Java and Bali, which has resulted from the subduction of the Australian plate beneath the Eurasian plate. For the first time since 1921 after eruptions finished and conditions seemed normal, on February 12, 2012, the status was upgraded to Alert based on changes in conditions. On 28 May 2012, it was lowered from 7 back to 6 (On a scale of 1-4)
The last major eruption on Galunggung was in 1982, which had a Volcanic Explosivity Index of 4 and killed 72 people. This eruption also brought the dangers of volcanic ash to aviation to worldwide attention, after two Boeing 747 passenger jets flying downwind of the eruption suffered temporary engine failures and damage to exterior surfaces, both planes being forced to make emergency landings at Jakarta airport.