Ash Cloud Causes More Travel Disruptions in Australia CheapOair Staff June 21, 2011 general Both Qantas Airlines and Virgin Australia have cancelled flights in Australia as the southern hemisphere continues to be affected by an ash cloud caused by a volcanic eruption. All flights to and from Melbourne and Sydney have been cancelled for the next 48 hours as the ash cloud, caused by Chile's Puyehue-Cordon volcano, makes its way around the planet for the second time. The ash cloud is currently hovering around 20,000 to 40,000 feet above sea level, making it too low for planes to fly under. Qantas stated on Tuesday it is company policy not to fly below the ash cloud due to high risks it was not comfortable taking, while Virgin said it would monitor the situation closely and make changes to their flight schedule as soon as possible. The ash cloud is expected to hover over Adelaide for the next 24 hours. Canberra, Melbourne and Sydney are expected to be stuck with the ash cloud for the next 36-48 hours.