Flying taxis ride again (Taxi! But not as you know it, 26 October). The dream of flying cars to overcome road congestion is almost as old as the automobile. It first emerged in 1901, and has been revived, though fortunately not realised, at intervals ever since. Le Corbusier’s City of Tomorrow featured skycars in 1929, as did Frank Lloyd Wright’s Broadacre City in 1930; in 1943, Scientific American predicted that after the war there would be “an airplane in every garage”; in 1999 the Moller Skycar offered “no traffic, no red lights, no speeding tickets”.

But none of them raised, let alone answered, the one fundamental question: why should traffic jams in the sky, mid-air collisions and constant noise above our heads be more desirable or less dangerous than the same things at ground level? The skies may look temptingly wide, but just wait till everyone’s up there!

Ruth Brandon

London

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