Apart from its uniqueness, Concorde is seen as a pace-setter because all other attempts to design such aircraft have relied on its delta wing design.

ECONOMIST: Supersonics on the back burner | The

The office is also in charge of the White House Communications Agency, which handles all presidential telephone, radio, and digital communications, as well as airlift operations through both fixed-wing and helicopter aircraft.

CENTERFORSECURITYPOLICY: Center For Security Policy

All this is difficult for aircraft-makers, who are used to being able to hang competing engines off the same wing.

ECONOMIST: Monitor