NASA has taken another step toward re-introducing supersonic flight with the award Tuesday of a contract for the design, building and testing of a supersonic aircraft that reduces a sonic boom to a gentle thump. Lockheed Martin Aeronautics Company of Palmdale, California, was selected for the Low-Boom Flight Demonstration contract, a cost-plus-incentive-fee contract valued at NASA has taken another step toward re-introducing supersonic flight with the award Tuesday of a contract for the design, building and testing of a supersonic aircraft that reduces a sonic boom to a gentle thump. Lockheed Martin Aeronautics Company of Palmdale, California, was selected for the Low-Boom Flight Demonstration contract, a cost-plus-incentive-fee contract valued at