GE says new engine answers need for speed

General Electric Co. has completed its initial design for the first commercial supersonic aircraft engine in five decades, a major hurdle for developing private planes — and perhaps eventually jetliners —that fly faster than the speed of sound. The twin-shaft, twin-fan design will slash travel times by hours following 50 years in which the average speed of private jets has increased only 10 per cent, GE said in a statement Monday.