While the release of a new production aircraft is a fairly rare event, the siren’s call of flight provides perennial inspiration for designers and futurists. Perhaps that explains why there is never a shortage of concept aircraft to capture our imaginations. Occasionally, there is already a flying prototype when we happen upon the concept; but more often than not, they exist only as renderings. Either way, these fanciful fliers — from supersonic jets to personal planes that take off vertically — are sure to elicit a “wow!” or two.