The case for London's third airport is based on several praiseworthy assumptions. That it will relieve the noise around London's airports; that Britain is running out of runways and terminal space. The case against Maplin is that the best way to reduce airport noise is to exploit the new quiet engines; that Maplin and all that goes with it, motorways, rail links, a new town, an industrial zone, a new port, all add up to an environmental disaster; that Britain is not now short of and may never run out of runways or terminal space; that Maplin is an economic folly.