If Concorde succeeds, her passengers will be hurled across the oceans at twice the height and twice the speed of today's jet travellers. In a few weeks her make-or-break test flights will begin. They will take up to three years to complete. But for the last ten years some of the best brain-power-and a lot of money-has been ploughed by Britain and France into the making of the Concorde. Tonight the planemakers tell their story of the race to be firs. with a supersonic transport-the story of the struggles, the promise, and the possible rewards. Produced by GLYN JONES "