Design and production challenges for a new, potentially stealthy airlifter loom large for the U.S. Air Force, the head of U.S. Transportation Command said on Thursday. Asked by Senate Armed Services Committee ranking member Jack Reed (D-R.I.) whether a strategic airlift program to replace the C-5M and C-17 could begin this year as a result of the upcoming Air Force fiscal 2027 budget request, Air Force Gen. Randall Reed responded that, while "strategic airlift is one of the most critical…