Ground staff stand as a Boeing Co. 787 Dreamliner aircraft operated by All Nippon Airways Co. (ANA), taxies to the company's hanger after a test flight at Haneda Airport in Tokyo, Japan, on Sunday, April 28, 2013. Boeing's 787 Dreamliner, which resumed flights after a more than three-month hiatus, is safe even while the cause of a battery defect remains uncertain, the aircraft manufacturer said. Photographer: Tomohiro Ohsumi/Bloomberg via Getty Images