Boeing could well get a second chance to bid for a $40 billion US Air Force tanker contract after a ruling by a government agency. ┬á The Government Accountability Office (GAO) has upheld Boeing's protest against the awarding of the air tanker deal to a rival consortium comprising Northrop Grumman and Airbus maker EADS. ┬á┬á "The Air Force made a number of significant errors that could have affected the outcome of what was a close competition,ÔÇØ the GAO said in a statement.