Original sentence: At some point though the forward speed of the plane combined with the rotational speed of the propeller will once again result in wave drag problems.In static and air tests, propfans reached a 30% improvement.Since the inside of the prop is moving more slowly than the outside, the blade became progressively more swept toward the outside, leading to a curved shape
Edited sentence: However this solution does not help as the plane itself accelerates; at some point the forward speed of the plane combined with the rotational speed of the propeller will once again result in wave drag problems.In static and air tests, propfans reached a 30% improvement without difficulty.Since the inside of the prop is turning more slowly than the outside, the blade became progressively more swept toward the outside, leading to a curved shape