A month ago, the world's largest passenger plane, described by one over-excited spotter as "bloody enormous", made a triumphant debut at London's Heathrow. Now, in two days, the double-decker A380, which can carry 840 passengers, has fallen to earth. EADS, majority owner of the superjumbo's maker, Airbus, lost €5bn (£3.4bn) or a quarter of its market value this week.