Australian airline Qantas shrugged off a safety scare involving its flagship A380 superjumbos to post a four-fold increase in half-year net profits to Aus$241 million ($240.6 million) on Thursday. Underlying profit before tax rose 56 percent to Aus$417 million, as sales grew 10 percent to Aus$7.59 billion over the second half of last year, despite November's mid-air engine blast that grounded the double-decker planes. "This result was achieved while overcoming significant operational challenges during the period including disruptions to the A380 network from November," Qantas said in a statement. In a sign aviation is recovering from the global downturn, Qantas flights raked in pre-tax profits of Aus$165 million, while budget offshoot Jetstar earned a record Aus$143 million. The company will not pay an interim dividend.