The world’s two civil aviation giants, Airbus and Boeing, today became the targets of World Trade Organisation probes, launched officially in Geneva to examine claims of illegal state aid.It could be the biggest trade battle in history. Boeing fired the first shot by making its first complaint to the WTO in October, and Airbus fired back. Now both the Americans and Europeans have repeated their complaints, an official inquiry is inevitable despite both sides insisting they will continue to talk. The row comes at a bad time as both the EU and America are trying to revive stalled talks on world trade in general, and it could strain transatlantic relations, although Brussels and Washington insist that will not happen. However it is likely to be a battle royal with billions of euros at stake. If either is found guilty, the other will be able to impose costly sanctions. No decision is likely before the end of the year, and an appeal is allowed.