Etihad Airways and NIKI, an airberlin group subsidiary airline, have announced the sale of joint codeshare flights. This follows December’s announcement that Etihad Airways had become airberlin’s largest single shareholder. From this week, Etihad Airways will place its EY code on NIKI (HG) operated flights from Frankfurt, Milan and Munich to the Austrian capital Vienna. Already, Etihad Guest frequent flyer programme members can earn Etihad Guest Miles on all NIKI operated flights.