Washington has pursued a complaint at the World Trade Organisation in Geneva alleging that Airbus has received illegal state aid for the development of new models. Airbus, which says it has received repayable loans, has levelled a countercharge against Boeing. The WTO is expected to rule on the case against Airbus first, but the two manufacturers remain locked in one of the bitterest trade disputes ever with no sign of a negotiated settlement. Huge issues that will test Airbus' mettle, for sure.